Effects of a Structured After-School Physical Activity Program on Physical Fitness, Body Composition, and Sleep in Primary School Students: A Quasi- Experimental Study

Effects of a Structured After-School Physical Activity Program on Physical Fitness, Body Composition, and Sleep in Primary School Students: A Quasi- Experimental Study | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Effects of a Structured After-School Physical Activity Program on Physical Fitness, Body Composition, and Sleep in Primary School Students: A Quasi- Experimental Study Guanjiankao Huang, Jinbao Yao, Lina Deng, Peixian Huang, Ping Hong, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7727089/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 11 Dec, 2025 Read the published version in BMC Public Health → Version 1 posted 19 You are reading this latest preprint version Abstract Background Physical inactivity is a significant public health issue among children. While compulsory physical education (PE) may be insufficient to meet daily activity recommendations, structured after-school physical activity (PA) programs have been proposed as a complementary strategy to promote health. This study aimed to investigate the effects of a 12-week after-school PA program on body composition, physical fitness, physical activity levels, and sleep outcomes in primary school students. Methods Thirty-four fourth-grade students from a primary school in Beijing were nonrandomly assigned to a control group (CG, n = 16, regular PE classes) or an experimental group (EG, n = 18, regular PE classes plus a structured after-school PA program, 5 times/week, 40 minutes/session) on the basis of their willingness to participate. Assessments were conducted at baseline, at mid-intervention, and post-intervention. The data were analyzed via two-way repeated-measures ANOVA, t-tests, and non-parametric tests. Results Body composition: The EG significantly reduced the waist‒to‒hip ratio ( F = 12.290, P < 0.05) and prevented the significant increases in body fat percentage and hip circumference observed in the CG ( F = 6.175, 14.431, both P < 0.05). Physical fitness and agility: The EG demonstrated significant improvements in sit-ups and sit-and-reach test results and multiple agility tests (e.g., 15-s burpee, F = 39.194, P < 0.05), outperforming the CG in several metrics. Physical activity: Time spent in moderate-to-vigorous PA (MVPA) significantly increased in the EG ( F = 8.270, P 0.05). Conclusion The after-school PA program effectively improved body composition, physical fitness, and daily MVPA levels but did not significantly impact sleep, suggesting that sleep may be more influenced by household routines and baseline patterns than structured afternoon activity. Trial registration: This study was registered prospectively in the Chinese Clinical Trial Registry (ChiCTR) on December 30, 2022 (Registration number: ChiCTR2200067241). After-school programme Body composition Physical fitness Physical activity Sleep Children 1. Background The “double reduction” policy, implemented in China in 2021, aims to alleviate the academic burden and reduce off-campus tutoring, creating new opportunities for integrating structured physical activities into after-school programs [ 1 ] . This policy provides a critical opportunity to integrate structured, school-based PA programs as a core component of the after-school service ecosystem, aiming to counteract the escalating childhood physical inactivity and obesity crisis. Despite this initiative, primary school students in China continue to face prevalent health issues such as obesity, physical inactivity, and excessive sedentary behavior [ 2 ] . Traditional physical education (PE) classes often fail to address these challenges because of limited content diversity and insufficient engagement [ 3 ] . Consequently, the development of engaging, structured, and sustainable after-school PA programs has emerged as an indispensable strategy to supplement mandatory PE and cultivate lifelong healthy habits. A substantial body of evidence has demonstrated the positive effects of school-based PA interventions on improving body composition, enhancing cardiorespiratory fitness, and increasing fundamental movement skills in children and adolescents [ 4 – 7 ] . However, a critical examination of the literature reveals two significant gaps. First, the majority of existing research has focused on in-class or curriculum-embedded interventions, with the potential of structured after-school programs within the unique Chinese “Double Reduction” context remaining underexplored. Second, and more notably, the impact of such programs on sleep—a pillar of child health—is highly equivocal. While some meta-analyses suggest that PA can promote longer sleep duration and improved sleep quality [ 8 ] , others report null findings, particularly for interventions conducted outside the evening window [ 9 , 10 ] . This inconsistency underscores the complex, multifaceted nature of sleep regulation, which can be influenced by activity timing, intensity, baseline sleep hygiene, and powerful confounding factors such as evening screen time and family routines [ 11 ] . The relationship between structured afternoon PA and objectively measured sleep parameters in Chinese children, who often face significant academic pressure, is therefore an open and pertinent question. On the basis of this context, this study conducted a comprehensive evaluation of the 12-week after-school program’s effects on a set of outcomes: body composition, physical fitness, agility, habitual PA, and sleep parameters. The aim of this study is to provide a holistic reference for optimizing after-school service programs and understanding their multifaceted impact on children’s health. 2. Methods 2.1. Subjects This study employed a nonrandomized quasi-experimental design and was conducted at a primary school in Mentougou District, Beijing, from September to December 2024. Fourth-grade students served as the research subjects and were divided into an experimental group and a control group on the basis of their willingness to participate. All participants were free of contraindications to exercise or severe chronic diseases. The sample size was calculated via G-Power 3.1.9.7 software on the basis of the primary outcome of physical fitness; repeated-measures ANOVA interaction effects with an effect size of f = 0.25, α = 0.05 (two-tailed), and statistical power (1-β) = 0.8 were selected. The calculated sample size was n = 28 (14 per group). The study ultimately enrolled 34 students: 18 in the experimental group (7 males, 11 females) and 16 in the control group (7 males, 9 females), meeting the sample size requirements. 2.2. Methods 2.2.1. After-School Physical Activity Program The after-school physical activity program was designed in accordance with the spirit of the “Guiding Opinions of the General Office of the Ministry of Education on Doing a Good Job in After-school Services for Primary and Secondary School Students” [ 12 ] and was tailored to the physical and mental development characteristics of fourth-grade students. The experimental group participated in a 12-week structured physical activity program consisting of 5 sessions per week, each lasting 40 minutes. The programme encompassed modules including aerobic exercise, strength training, flexibility, and agility (details in Table 1 ). The control group engaged in self-supervised free activities after school. These free activities were unstructured and took place in common school areas such as classrooms, libraries, or playgrounds. Students were permitted to choose rest, quiet study, social interaction, or light physical play at their own discretion under the general supervision of school staff for safety and order. The research team did not monitor or record the daily activities of this group; instead, group differences were compared solely through post-intervention physical fitness tests, thereby ensuring the validity of the comparison with the experimental group that received the structured exercise intervention. Table 1 Arrangement of the after-school physical activity program for primary school students Session Arrangement Contents Sessions/Week Duration (min) Intensity (% of Max HeartRate) Warm-up Jogging/Joint Preparation/Warm-up Games 5 5 —— Aerobic/Strength/Flexibility Training Relay Run/Endurance Run/Rope Skipping/Dribble Relay/Maximum Stretch/Squat Jump/Superman Exercise/Plank, etc. 3 30 60%~80% Agility Training W-shaped/T-shaped/Z-shaped/Y-shaped/Cross/Fan/Triangle Direction Change Run/Agility Ladder Steps 2 30 60%~70% Cool-down Cool-down Exercises 5 5 —— 2.2.2. Body composition indicator measurement and classification standards Body composition indicators included weight, body mass index (BMI), waist circumference, hip circumference, waist‒hip ratio, and body fat percentage. Height, weight, waist circumference, and hip circumference are measured by professionals, whereas body fat percentage is assessed via a body composition analyzer (Sihai Huachen, Shanghai). BMI = weight (kg)/height² (m²), WHR = waist circumference (cm)/hip circumference (cm). Overweight and obesity in children and adolescents are defined via the “Chinese BMI Screening and Classification Standards for Overweight and Obesity in Children and Adolescents” [ 13 ] . 2.2.3. Physical Fitness Indicator Measurement These include 1-minute sit-ups, 1-minute rope skipping, sit-and-reach, standing long jump, 50 m sprint, and 50 m×8 shuttle runs. All indicators were tested according to the National Student Physical Health Standard (Revised 2014) [ 14 ] . 2.2.4. Agility Indicator Measurement The tests included the t-test, Illinois agility test, 15-s burpee test, 15-s four-square jump test, 5-0-5 agility test, hexagon jump test, and hexagon reaction ball test. Each indicator was determined through a literature review and expert consultation. 2.2.5. Physical Activity and Sleep Assessment The Actigraph GT3X accelerometer (worn on the right hip) measured participants’ physical activity and sedentary and sleep behavior over 7 days (including 5 school days + 2 weekend days), which were removed only during aquatic activities. The data were collected from 00:00 on the distribution day until the device returned on day 8, with 10-second sampling intervals. The data were analyzed via ActLife 6.5 software. The valid wear time was screened on the basis of Choi’s criteria [ 15 ] , and activity levels were categorized according to the intensity thresholds proposed by Zhu et al. [ 16 ] Chinese children and adolescents engaged in sedentary behavior (SB), low-intensity physical activity (LPA), moderate-intensity physical activity (MPA), and vigorous-intensity physical activity (VPA), with cutoff points of 100, 2800, and 4000 counts per minute, respectively. (VPA). Moderate-to-vigorous physical activity (MVPA) = moderate physical activity (MPA) + vigorous physical activity (VPA). All analyses excluded data from after-school sports service periods. Sleep data processing employs the Sedah algorithm [ 17 ] , which is suitable for pediatric and adolescent sleep. It primarily utilizes accelerometer data collected at 60-second intervals and a fully automated algorithm validated against 24-hour waist–worn accelerometer measurements. Selected metrics from the measured data—including sleep onset time, sleep offset time, sleep period, sleep efficiency, wake after sleep onset (WASO), number of arousals, and average awaking time—serve as the sleep parameters for analysis in children and adolescents. 2.2.6. Data collection This study conducted three data collection sessions in September (baseline), November (midterm), and December (endterm) 2024. The specific testing schedule was as follows: body composition was assessed in September and December (pre- and post-intervention); physical fitness, agility, physical activity levels (experimental group), and sleep (experimental group) were measured at all three time points. This approach balanced data completeness with economic conditions (e.g., minimizing invasive blood draws). The detailed collection protocols are outlined in Table 2 . Table 2 Schedule of Data Collection for Each Indicator Category of Indicators Specific indicators Testing Time Points for the Experimental Group Testing Time Points for the Control Group Notes Body Composition Body Weight, BMI, Body Fat Percentage, etc. Sep, Dec Sep, Dec Body composition metrics change slowly, with only pre- and postmeasurements conducted. Physical Fitness and Agility 50-m sprint, T-test, etc. Sep, Nov, Dec Sep, Nov, Dec Measured at three time points to monitor dynamic changes in physical performance. Physical Activity and Sleep MVPA, SB, sleep period, etc. (ActiGraph GT3X) Sep, Nov, Dec --- Accelerometers are expensive, and only the experimental group wore them. 2.2.7. Quality Control Service protocols are designed and implemented by the Sports Medicine and Physical Education team at Beijing Sport University to ensure service quality and safety. All the researchers underwent standardized training before conducting testing and data collection. The impact of dietary confounding factors is minimized through home health education (the distribution of advocacy materials and nutrition manuals). Data undergo dual entry and cross-verification to ensure accuracy. 2.2.8. Statistical methods Data analysis was performed via SPSS 26.0. Continuous variables were assessed for normality via the Shapiro‒Wilk test. Data are presented as the mean ± standard deviation (SD) for normally distributed variables and were compared via the independent samples t-test; nonnormally distributed variables are expressed as the median (interquartile range, IQR) and were compared via the Mann‒Whitney U test. Changes in body composition, physical fitness, and agility indicators between the two groups of elementary school students were compared via two-way repeated-measures ANOVA. When interaction effects were present, simple effects analysis was performed. Changes in physical activity and sleep indicators within the experimental group were compared via one-way repeated-measures ANOVA. A P value < 0.05 was considered statistically significant. 3. Results 3.1. Baseline characteristics There were no statistically significant differences in baseline body composition, physical fitness, or agility indicators between the two groups of students (Tables 3 , 4 , 5 ) (all P > 0.05), indicating comparability at the start of the intervention. Table 3 Comparison of body composition indicators at baseline among primary school students in the two groups ( \(\:\stackrel{-}{x}\) ±s) Group N Height (cm) Weight (kg) BMI/(kg*m − 2) Body fat (%) Waist circumference (cm) Hip circumference (cm) Waist-to-hip ratio CG 16 143.06 ± 8.50 34.65(28.25 ~ 46.65) 17.03(15.06 ~ 20.47) 22.21 ± 9.38 57.00(52.98 ~ 72.58) 77.26 ± 9.90 0.81 ± 0.06 EG 18 139.61 ± 7.55 33.25(29.20 ~ 47.65) 18.19(15.16 ~ 24.42) 26.99 ± 12.29 65.15(56.07 ~ 77.10) 80.31 ± 12.05 0.85 ± 0.07 t/z value 1.253 -0.053 -0.752 -1.264 -0.840 -0.801 -1.496 P value 0.219 0.958 0.452 0.215 0.401 0.429 0.144 Note: Data are presented as the means ± SDs or medians (IQRs); p values were obtained from independent samples t tests (normally distributed data) or Mann‒Whitney U tests (nonnormally distributed data). Table 4 Comparison of physical fitness indicators at baseline among primary school students in the two groups ( \(\:\stackrel{-}{x}\) ±s) Group n 1-min sit-ups (reps) 50 m sprint (s) 1-min rope skipping (reps) Sit-and-reach (cm) Standing long jump (cm) 50 m×8 shuttle run (s) CG 16 34.56 ± 11.75 10.51(10.13 ~ 11.71) 145.38 ± 31.48 12.21 ± 5.27 148.00 ± 21.27 134.02(115.06 ~ 155.71) EG 18 33.22 ± 13.17 10.74(10.03 ~ 11.82) 138.56 ± 30.04 14.16 ± 6.31 141.56 ± 16.1 132.37(124.80 ~ 147.29) t/z value 0.306 -0.069 0.646 -0.970 1.003 -0.276 P value 0.761 0.945 0.523 0.339 0.323 0.783 Note: Data are presented as the means ± SDs or medians (IQRs); p values were obtained from independent samples t tests (normally distributed data) or Mann‒Whitney U tests (nonnormally distributed data). Table 5 Comparison of agility indicators at baseline among primary school students in the two groups ( \(\:\stackrel{-}{x}\) ±s) Group N T test (s) Illinois agility run (s) 15-s Burpee (reps) 15-s Four- Square Jump (reps) 5-0-5 Agility Test (s) Hexagon Jump (s) Hexagon Reaction Ball Test (s) CG 16 17.37 ± 2.54 20.41 ± 1.16 8.44 ± 1.15 30.25 ± 8.91 3.06(2.96 ~ 3.17) 16.52(15.43 ~ 18.12) 1.08 ± 0.44 EG 18 18.04 ± 3.06 20.67 ± 1.66 8.00 ± 1.28 24.89 ± 8.09 3.10(2.91 ~ 3.30) 18.35(17.00 ~ 18.93) 1.24 ± 0.40 t/z value 0.685 0.504 -1.040 -1.839 -0.385 -1.855 1.124 P value 0.499 0.618 0.306 0.075 0.700 0.064 0.269 Note: Data are presented as the means ± SDs or medians (IQRs); p values were obtained from independent samples t tests (normally distributed data) or Mann‒Whitney U tests (nonnormally distributed data). 3.2. Effects on Body Composition The results indicate that the main effects of time on height, weight, BMI, body fat percentage, hip circumference, and waist‒to-hip ratio were statistically significant, with post-test values higher than pre-test values for all indicators; the interaction effects for weight and waist circumference were statistically significant ( F = 101.625, 67.577, 31.849, 9.545, 16.902, 9.932, 4.551, 4.996; all P < 0.05), whereas the main effects of group were not statistically significant. Further simple effect analysis revealed no significant changes in post-test body fat percentage or hip circumference in the experimental group compared with the pre-test group ( F = 3.489, 3.856; both P > 0.05), whereas both measures significantly increased in the control group ( F = 6.175, 14.431; both P < 0.05); the waist‒hip ratio in the experimental group decreased significantly at post-test compared with pre-test ( F = 12.290, P 0.05). (Table 6 ). Table 6 Comparison of body composition indicators between primary school students in the two groups before and after the intervention ( \(\:\stackrel{-}{x}\) ±s) Group Test time N Height (cm) Weight (kg) BMI/(kg*m − 2) Body fat (%) Waist circumference (cm) Hip circumference (cm) Waist-to-hip ratio Control Pre 16 143.06 ± 8.50 37.76 ± 12.44 18.09 ± 4.22 22.21 ± 9.38 63.12 ± 11.96 77.26 ± 9.90 0.81 ± 0.06 Post 16 144.63 ± 8.76 40.21 ± 13.37 18.84 ± 4.43 23.59 ± 9.61 64.11 ± 11.96 79.46 ± 9.85 0.80 ± 0.06 Experimental Pre 18 139.61 ± 7.55 40.91 ± 15.19 20.61 ± 6.01 26.99 ± 12.29 68.54 ± 14.73 80.31 ± 12.05 0.85 ± 0.07 Post 18 141.00 ± 7.84 42.46 ± 15.27 20.99 ± 5.82 27.98 ± 10.80 66.93 ± 15.63 81.38 ± 10.99 0.81 ± 0.09 P 1 -value 0.000 0.000 0.000 0.004 0.600 0.000 0.004 P 2 -value 0.214 0.583 0.203 0.217 0.387 0.504 0.356 P 3 -value 0.544 0.041 0.069 0.602 0.033 0.166 0.107 Note: P 1 indicates the main effect of time, P 2 indicates the main effect of group, and P 3 indicates the interaction effect. 3.3. Effects on physical fitness The results indicate statistically significant interaction effects for the 1-min sit-ups, 50-m sprint, sit-and-reach, and 50 m × 8 shuttle run tests ( F = 5.052, 3.594, 6.641, 4.026; all P < 0.05). The main effects of time on the 1-min sit-ups and sit-and-reach test results were statistically significant ( F = 6.504, 3.103; both P < 0.05). Further simple effect analysis revealed that the experimental group demonstrated superior mid-test and post-test results compared with the pre-test results for both the 1-min sit-ups and sit-and-reach groups ( F = 11.001, 6.992; both P < 0.01), with post-test sit-and-reach scores significantly exceeding those of the control group (mean difference: 5.736 ± 1.721 cm, P < 0.01). The experimental group’s post-test results for 1-min rope skipping were superior to the pre-test results, whereas the mid-test results for the 50 m×8 shuttle run were better than the pre-test results. Additionally, the post-test results for the 50-m sprint group outperformed those of the control group ( F = 3.088, 4.119, 3.559; P = 0.053, 0.062, 0.068). Although these results did not reach statistical significance, the P values approached 0.05, suggesting that these effects may have potential statistical significance. (Table 7 ). Table 7 Comparison of physical fitness indicators of primary school students between the two groups on the pre-, mid-, and post-test ( \(\:\stackrel{-}{x}\) ±s) Group Test time N 1-min sit-ups (reps) 50 m sprint (s) 1-min rope skipping (reps) Sit-and-reach (cm) Standing long jump (cm) 50 m×8 shuttle run (s) Control Pre 16 34.56 ± 11.75 10.89 ± 1.34 145.38 ± 31.48 12.21 ± 5.27 148.00 ± 21.27 135.94 ± 21.09 Mid 16 34.13 ± 10.89 11.36 ± 1.51 149.81 ± 33.98 10.33 ± 4.82 151.19 ± 19.53 135.43 ± 21.57 Post 16 36.88 ± 11.92 12.34 ± 1.06 146.19 ± 28.80 9.78 ± 4.50 147.44 ± 16.82 140.26 ± 19.36 Experimental Pre 18 33.22 ± 13.17 13.83 ± 9.66 138.56 ± 30.04 14.16 ± 6.31 141.56 ± 16.10 137.58 ± 20.93 Mid 18 38.00 ± 11.60 11.22 ± 1.88 146.06 ± 25.58 13.38 ± 6.13 144.72 ± 15.92 145.42 ± 35.97 Post 18 38.50 ± 9.67 11.10 ± 2.44 155.44 ± 34.83 15.51 ± 5.42 144.72 ± 14.82 140.11 ± 38.13 P 1 -value 0.004 0.384 0.122 0.008 0.294 0.319 P 2 -value 0.715 0.593 0.964 0.053 0.352 0.676 P 3 -value 0.013 0.035 0.173 0.002 0.568 0.028 Note: P 1 indicates the main effect of time, P 2 indicates the main effect of group, and P 3 indicates the interaction effect. 3.4. Effects on Agility The results indicate that the interaction effects for the 15-s burpee, 15-s four-square, and hexagon jumps were statistically significant ( F = 10.286, 4.564, and 6.368; all P < 0.05). The main effects of time for the t-test, Illinois agility run, 15-s burpee, 15-s four-square jump, 5-0-5 agility test, and hexagon jump were statistically significant ( F = 10.167, 4.186, 26.228, 85.831, 9.310, 38.100; all P < 0.05). The main effects of group on the 15-s burpee and hexagon reaction ball tests were statistically significant ( F = 4.445, 6.028; both P < 0.05). Further simple effects analysis revealed that the experimental group demonstrated superior mid-test and post-test scores compared with pre-test scores in the T-test, 15-s burpee, 15-s four-square jump, and hexagonal jump ( F = 7.262, 39.194, 51.245, 38.331; P < 0.05). Moreover, the experimental group demonstrated superior mid-test performance compared with the control group in the 15-s burpee, hexagon jump, and hexagonal reaction ball tests (mean differences: 2.028 ± 0.577 reps, -0.142 ± 0.633 s, and − 0.202 ± 0.099 s; F = 12.369, 4.969, and 4.093; all P < 0.05). The post-test results for the 5-0-5 agility test in the experimental group were superior to those of the control group (mean difference: 0.187 ± 0.086 s; F = 4.749; P < 0.05). (Table 8 ). Table 8 Comparison of sensitivity indicators of primary school students between the two groups on the pre-, mid-, and post-test ( \(\:\stackrel{-}{x}\) ±s) Group Test time N T-test (s) Illinois Agility Run (s) 15-s Burpee (reps) 15-s four-square jump (reps) 5-0-5 Agility test (s) Hexagon jump (s) Hexagon Reaction Ball Test (s) Control Pre 16 17.37 ± 2.54 20.48 ± 1.16 8.44 ± 1.15 30.25 ± 8.91 3.07 ± 0.12 17.09 ± 2.46 1.08 ± 0.44 Mid 16 16.56 ± 2.06 19.81 ± 1.20 8.75 ± 0.93 39.50 ± 7.80 2.99 ± 0.19 16.06 ± 2.44 0.96 ± 0.39 Post 16 17.44 ± 1.85 20.34 ± 1.23 9.56 ± 1.09 40.25 ± 6.39 3.28 ± 0.29 15.08 ± 3.30 0.98 ± 0.33 Experimental Pre 18 18.04 ± 3.06 20.58 ± 1.64 8.00 ± 1.28 24.89 ± 8.09 3.13 ± 0.36 18.77 ± 2.80 1.24 ± 0.40 Mid 18 15.89 ± 1.75 20.20 ± 1.53 10.78 ± 2.13 39.33 ± 4.07 3.06 ± 0.18 14.65 ± 1.06 1.16 ± 0.13 Post 18 16.34 ± 1.65 20.02 ± 1.32 10.56 ± 1.88 41.11 ± 5.40 3.10 ± 0.18 14.20 ± 1.61 1.03 ± 0.10 P 1 -value 0.000 0.020 0.000 0.000 0.001 0.000 0.212 P 2 -value 0.574 0.887 0.012 0.441 0.138 0.762 0.035 P 3 -value 0.091 0.164 0.000 0.000 0.203 0.027 0.473 Note: P 1 indicates the main effect of time, P 2 indicates the main effect of group, and P 3 indicates the interaction effect. 3.5. Effects on the physical activity levels of the experimental groups Eleven participants in the experimental group completed physical activity monitoring. After excluding after-school sports service periods, both their daily moderate-intensity physical activity (MPA) and moderate-to-vigorous physical activity (MVPA) times significantly improved ( F = 26.178, 8.270; both P < 0.01). The MPA levels at both the mid-test and post-test were greater than those at the pretest, with the MPA level at the mid-test exceeding that at the post-test (both P < 0.05); the MPA level at the mid-test was greater than that at the pre-test ( P < 0.05). However, no significant changes were observed in sedentary behavior (SB), low-intensity physical activity (LPA), or vigorous-intensity physical activity (VPA) duration ( F = 4.721, 0.097, 0.681; all P > 0.05), as shown in Table 9 . Table 9 Comparison of physical activity indicators of primary school students in the experimental group on the pre-, mid-, and post-test ( \(\:\stackrel{-}{x}\) ±s) Group Test time N SB (min/day) LPA (min/day) MPA (min/day) VPA (min/day) MVPA (min/day) Experimental Pre 11 413.26 ± 89.03 436.42 ± 42.40 16.82 ± 5.75 13.38 ± 7.81 30.20 ± 11.97 Mid 11 394.48 ± 94.23 432.16 ± 47.46 27.32 ± 7.97 a 12.56 ± 5.54 39.88 ± 12.21 a Post 11 441.52 ± 78.76 438.97 ± 51.00 21.79 ± 7.66 ab 11.54 ± 5.39 33.33 ± 11.65 P value 0.089 0.899 0.000 0.509 0.003 Note: SB: sedentary behavior; LPA: light physical activity; MPA: moderate physical activity; VPA: vigorous physical activity; MVPA: moderate to vigorous physical activity. a Significantly different from baseline, P < 0.05; b significantly different from the middle test, P < 0.05. All pairwise comparisons were adjusted via the Bonferroni correction. 3.6. Effects on Sleep Parameters in the Experimental Group Twelve participants in the experimental group completed sleep monitoring. No significant changes were observed from baseline to post-intervention in sleep onset time, sleep offset time, sleep period, sleep efficiency, WASO, number of arousals, or average awaking time ( F = 0.828, 0.186, 0.975, 0.542, 0.625, 0.164, 1.251; all P > 0.05), as shown in Table 10 . Table 10 Comparison of sleep indicators among primary school students in the experimental group on the pre-, mid-, and post-test ( \(\:\stackrel{-}{x}\) ±s) Group Test time N Sleep onset time Sleep offset time Sleep period (min) Sleep efficiency (%) WASO (min) Number of arousals Average awaking time (min) experimental Pre 12 22:10 ± 0:32 7:17 ± 0:36 533.40 ± 33.33 97.57 ± 1.20 13.59 ± 6.71 5.49 ± 2.87 2.33 ± 1.03 Mid 12 21:58 ± 0:32 7:14 ± 0:23 540.71 ± 43.34 97.07 ± 1.83 16.16 ± 10.06 5.69 ± 3.09 2.58 ± 1.00 Post 12 22:09 ± 0:39 7:19 ± 0:26 535.79 ± 43.99 97.35 ± 1.86 14.37 ± 9.80 6.06 ± 3.67 2.21 ± 0.59 P value 0.419 0.815 0.410 0.587 0.541 0.845 0.305 Note: WASO: Wake After Sleep Onset. 4. Discussion 4.1 The After-School PA Program Improved Primary School Students’ Body Composition The prevalence of overweight and obesity in children and adolescents has become a major public health concern in recent decades [ 18 ] . The results of the body composition test performed in our study also indicate that the EG maintained a stable body fat percentage and hip circumference while reducing the waist‒hip ratio, whereas the CG showed increasing trends across all the metrics. These findings suggest that after-school physical activity effectively inhibits abdominal fat accumulation, which is consistent with existing research showing that exercise improves body composition [ 19 , 20 ] . Notably, the increases in BMI and body fat percentage observed in both groups may be attributed to the following factors: 1) Children aged 9–10 are in the growth and development phase, where weight and body fat gain represent normal physiological phenomena [ 21 ] ; 2) According to a systematic review by Zhu Zhiqiang et al., exercise interventions lasting over 60 minutes per session three times weekly for at least 12 weeks can significantly improve body composition in children and adolescents [ 22 ] . The intervention period in this study may not have reached the optimal duration. 3) Increased physiological fat storage requirements during autumn and winter may also contribute to elevated body fat levels [ 23 ] . 4.2 The After-school PA Program Enhanced Primary School Students’ Physical Fitness and Agility Ability With respect to physical fitness and agility indicators, the EG showed significant improvements in metrics such as the 50-m sprint, sit-up, sit-and-reach, and several agility ability results (t-test, etc.), indicating that after-school physical activity effectively promoted the development of multiple athletic abilities in primary school students. This result aligns with the conclusions of studies by Neil-Sztramko et al. and Zhang Bin et al. [ 24 , 25 ] . However, improvements in explosive power (standing long jump) and endurance fitness (50×8 m shuttle run) were less pronounced. One possible reason is related to testing conditions: cold, windy winter weather may have impacted performance, as previous studies indicate that cold temperatures inhibit athletic ability [ 26 ] . On the other hand, the sensitive period for strength development typically occurs between ages 10–12 for girls and 12–14 for boys, whereas endurance development peaks between ages 16–18 [ 27 ] . Fourth-grade students have not yet entered these sensitive periods, necessitating more scientifically designed training programs aligned with their developmental characteristics in the future. Nevertheless, under the “double reduction” policy, after-school sports programs remain a vital avenue to compensate for insufficient traditional physical education class time [ 28 , 29 ] . The specialized training designed in this study—including aerobic, strength, and agility exercises—significantly supplements standard physical education curricula. This enriches the physical education system and comprehensively enhances students’ athletic capabilities. 4.3 The After-School PA Program Enhanced Primary School Students’ Physical Activity Levels With respect to physical activity indicators, students in the experimental group exhibited a significant increase in moderate-to-vigorous physical activity (MVPA) time outside the designated after-school sports service period. This finding indicates that after-school sports services not only directly increase structured exercise time but also, more importantly, foster the development of students’ daily autonomous physical activity habits, with profound implications for promoting healthy behaviors. Second, although MVPA slightly declined after peaking at the mid-term assessment, it remained significantly higher than the baseline levels. This finding suggests that the intervention may have produced sustained behavioral changes, which is consistent with findings from previous similar studies [ 24 , 30 ] . The intervention program in this study achieved the core objective of the “double reduction” policy [ 31 ] , namely, increasing students' participation time in physical activities through systematic after-school sports services. 4.4 Null Effect of the After-School PA Program on Sleep Behavior The present study revealed no significant alterations in sleep behavior following the 12-week after-school sports service intervention, as measured by objective actigraphy metrics, including total sleep time, sleep efficiency, and the WASO. Several factors may explain the stability of the sleep parameters. First, the intervention was conducted immediately after school at 3:30 p.m. and concluded at 4:10 p.m., leaving a considerable gap between activity and bedtime. The acute effects of exercise on sleep architecture (e.g., increasing slow-wave sleep) may have dissipated at night [ 10 , 32 ] . Second, the existing sleep patterns of the participant cohort may have played a role. The baseline data indicated that the children were already obtaining close to the recommended 9–11 hours of sleep per night for their age group [ 33 ] , potentially leaving little room for significant improvement (a ceiling effect). Furthermore, the structured nature of the intervention, while beneficial for physical activity, may not have addressed the primary drivers of sleep behavior in children, which are often strongly influenced by established household routines, parental rules regarding bedtime, and screen time usage in the evenings [ 11 ] . It is important to distinguish between the objective measures of sleep duration and efficiency reported here and potential subjective improvements in sleep quality that were not captured. The participants anecdotally reported feeling more rested, a discrepancy that suggests that actigraphy may not fully capture the perceived restorative benefits of physical activity. Future research could benefit from incorporating subjective sleep diaries or parent-reported measures to triangulate findings. 4.5 Limitations and Future Perspectives This study received support from multiple stakeholders, including primary schools, medical institutions, physical education universities, communities, and families. However, several practical issues emerged during implementation. First, owing to academic pressure and varying parental cooperation levels, the sample was drawn from a single grade level and was nonrandomly grouped. This may limit the generalizability of the findings and introduce selection bias. Methodologically, low accelerometer wear compliance led to high dropout rates in physical activity and sleep data, highlighting the practical difficulties of objectively monitoring physical behavior in this population. Nevertheless, the study yielded significant findings: after-school sports services effectively improved body composition (e.g., reducing the waist-to-hip ratio) and enhanced athletic qualities such as speed, strength, and agility while substantially increasing students’ moderate-to-vigorous physical activity time. According to social ecology theory, individual behavior is influenced by multilevel environmental factors [ 34 ] , with younger students’ behavior being particularly dependent on family support. Future efforts should strengthen parental health education to increase their recognition of and cooperation with professional service teams. Concurrently, establishing standardized certification mechanisms for after-school sports services will promote the development of a collaborative “family-school-community” system. This comprehensive approach will increase the implementation quality and monitoring effectiveness of after-school sports services, thereby holistically advancing children’s healthy development. 5. Conclusions The 12-week structured after-school physical activity program effectively improved body composition, enhanced physical fitness and agility, and increased daily moderate-to-vigorous physical activity levels in primary school students. However, the program did not induce significant changes in objective sleep parameters. This suggests that while such programs are highly beneficial for physical health, positively impacting sleep in children who already have sufficient sleep duration may require interventions that more directly target evening routines and the home environment, in addition to providing daytime PA. Abbreviations The following abbreviations are used in this manuscript: ANOVA Analysis of variance BMI Body mass index CG Control Group EG Experimental group IQR Interquartile range LPA Light physical activity MPA Moderate physical activity MVPA Moderate-to-vigorous physical activity PA Physical activity PE Physical education SB Sedentary behavior SD Standard deviation VPA Vigorous physical activity WASO Wake after sleep onset WHR Waist-to-hip ratio Declarations Ethics approval and consent to participate: Written informed consent was obtained from all parents/guardians, and assent was obtained from all students. The protocol was approved by the Biomedical Research Ethics Committee of Peking University First Hospital (Approval No. : 2022 Yan 553-003-Amendment) and was conducted in accordance with the Declaration of Helsinki. Consent for publication: Not applicable. No individual data or information is provided; thus, the need for individual consent for publication is negated. Availability of data and materials: The datasets supporting the conclusions of this article are available in the Open Science Framework (OSF) at https://doi.org/10.17605/OSF.IO/F9EZG. C ompeting interest s: The authors declare that they have no conflicts of interest. Funding: This research was funded by the Beijing Association of Holistic Integrative Medicine, grant number ZH-2024-2742. The APC was funded by the same grant. Author s’ Contribution s: PH and XML were responsible for the conception and design of the study. GJKH, JBY, LND and PXH were responsible for the implementation of the study. GJKH, JBY and LND managed the data collection and analysis activities. GJKH and JBY were major contributors in writing the manuscript. GJKH and XML revised the final version of the manuscript. All authors read and approved the final manuscript. Acknowledgments: The authors would like to extend their sincere gratitude to all the students who participated in this study, as well as their parents and teachers , for their invaluable cooperation and support. The authors are also grateful for the support from the Department of Endocrinology at Peking University First Hospital for their essential medical assistance and support throughout this research. Authors’ information: No additional information is necessary. References General Office of the Central Committee of the Communist Party of China, General Office of the State Council. Opinions on further reducing the burden of homework for students in compulsory education and the burden of out-of-school training B/0L]. 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(in Chinese) Tracy, D.J.; Xu, Z.; Choi, L.; et al. Separating bedtime rest from activity using waist or wrist-worn accelerometers in youth[J]. PLOS One , 2014, 9(4): e92512. Zhu, Z.; Chen, P.; Zhuang, J. Intensity classification accuracy of accelerometer-measured physical activities in Chinese children and youth[J]. Res Q Exerc Sport, 2013, 84 Suppl 2: S4-11. Sadeh, A.; Sharkey, K.M.; Carskadon, M.A. Activity-based sleep-wake identification: an empirical test of methodological issues[J]. Sleep , 1994, 17(3): 201-207. DOI: 10.1093/sleep/17.3.201. Lister, N.B.; Baur, L.A.; Felix, J.F.; et al. Child and adolescent obesity[J]. Na t. Rev. Dis . Primers, 2023, 9(1): 24. Wang, Y.T.; Guo, X.Y.; Du, H.Z.; et al. Body Composition Profiles and Associated Factors in Adolescents Undergoing Long-term Regular Exercise[J]. Med . J . PUMCH , 2025, 16(03): 591-597 (in Chinese) Armstrong, A.; Jungbluth Rodriguez, K.; Sabag, A.; et al. Effect of aerobic exercise on waist circumference in adults with overweight or obesity: a systematic review and meta-analysis[J]. Obes . Rev . 2022, 23(8): e13446. Cheng, K.; Wang, B.X.; Wang, C.H.; et al. Correlation between body composition and bone mineral density in children and adolescents aged 5-14 years[J]. Chin . J . Child Health Care , 2024, 32(08): 844-849 (in Chinese) Zhu, Z.Q.; Xu, Q.L.; Shao, X.Y.; et al. Health benefits of physical activity for obese and overweight children: a systematic review of systematic reviews[J]. Chin J Rehabil Theory Pract , 2025, 31(03): 296-305(in Chinese) Shen, Z.L.; Yang, Y.L.; Sun, B.; et al. Effect of ambient temperature on arginine vasopressin-induced hypothermia in rats and its relationship with grooming behavior and brown adipose tissue thermogenesis[J]. J Chengdu Med Coll , 2011, 6(01): 20-23 (in Chinese) Neil-Sztramko, S.E.; Caldwell, H.; Dobbins, M. School-based physical activity programs for promoting physical activity and fitness in children and adolescents aged 6 to 18[J]. Cochrane Database Syst Rev , 2021, 9(9): CD007651. Zhang, B.; Li, L.; Wang, M.D.; et al. Effects of after-school exercise service on physical fitness in primary school students[J]. Chin J Sch Health, 2024, 45(02): 253-257. (in Chinese) Atkin, A.J.; Sharp, S.J.; Harrison, F.; et al. Seasonal variation in children’s physical activity and sedentary time[J]. Med Sci Sport Exer , 2016, 48(3): 449-456. Zhang, C.Y. Adolescent Physical Fitness Sensitive Periods and Exercise Methods[J]. J Chin Youth Soc Sci , 2014, 33(5): 68-70. (in Chinese) Li, Y.R.; Dang, X.N. Current Situation, Problems and Optimization of After-School Sports Service for Primary and Secondary School Students Under the "Double Reduction" Policy[J]. J Chengdu Sport Univ , 2022, 48(06): 51-56. (in Chinese) Wu, J.F.; Xu, Y.Y. Current situation and countermeasures of extracurricular sports activities in primary and secondary schools under the "Double Reduction" policy[J]. Sports World, 2023(7): 91-93. (in Chinese) Must, A.; Tybor, D.J. Physical activity and sedentary behavior: a review of longitudinal studies of weight and adiposity in youth[J]. Int J Obe . 2005, 29 Suppl 2: S84-96. DOI: 10.1038/sj.ijo.0803062. Liu, H.Y.; Shan, S. Reflections on implementing the policy of "No Less Than 2 Hours of Comprehensive Physical Activity per Day for Primary and Secondary School Students"[J]. J Phys Educ , 2025, 32(02): 1-11 (in Chinese) Miller, D.J.; Roach, G.D.; Lastella, M.; et al. Hit the gym or hit the hay: can evening exercise characteristics predict compromised sleep in healthy adults?[J]. Front. Physiol. 2023, 14: 1231835. Tremblay, M.S.; Carson, V.; Chaput, J.P.; et al. Canadian 24-hour movement guidelines for children and youth: an integration of physical activity, sedentary behavior, and sleep[J]. Appl. Physiol. Nutr. Metab. 2016, 41(6 Suppl 3): S311-327. Liang, W.; He, Y.X.; Su, N.; et al. Analysis of social-ecological factors influencing the development of fundamental motor skills among overweight and obese children[J]. Chin J Sch Health , 2024, 45(09): 1328-1333, 1339. (in Chinese) Additional Declarations No competing interests reported. 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16:18:53","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1858489,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7727089/v1/8101ee72-0ad0-4a34-b7cf-d74c58ab8cda.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Effects of a Structured After-School Physical Activity Program on Physical Fitness, Body Composition, and Sleep in Primary School Students: A Quasi- Experimental Study","fulltext":[{"header":"1. Background","content":"\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe \u0026ldquo;double reduction\u0026rdquo; policy, implemented in China in 2021, aims to alleviate the academic burden and reduce off-campus tutoring, creating new opportunities for integrating structured physical activities into after-school programs\u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. This policy provides a critical opportunity to integrate structured, school-based PA programs as a core component of the after-school service ecosystem, aiming to counteract the escalating childhood physical inactivity and obesity crisis. Despite this initiative, primary school students in China continue to face prevalent health issues such as obesity, physical inactivity, and excessive sedentary behavior \u003csup\u003e[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e. Traditional physical education (PE) classes often fail to address these challenges because of limited content diversity and insufficient engagement\u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e. Consequently, the development of engaging, structured, and sustainable after-school PA programs has emerged as an indispensable strategy to supplement mandatory PE and cultivate lifelong healthy habits.\u003c/p\u003e\u003cp\u003eA substantial body of evidence has demonstrated the positive effects of school-based PA interventions on improving body composition, enhancing cardiorespiratory fitness, and increasing fundamental movement skills in children and adolescents\u003csup\u003e[\u003cspan additionalcitationids=\"CR5 CR6\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e. However, a critical examination of the literature reveals two significant gaps. First, the majority of existing research has focused on in-class or curriculum-embedded interventions, with the potential of structured after-school programs within the unique Chinese \u0026ldquo;Double Reduction\u0026rdquo; context remaining underexplored. Second, and more notably, the impact of such programs on sleep\u0026mdash;a pillar of child health\u0026mdash;is highly equivocal. While some meta-analyses suggest that PA can promote longer sleep duration and improved sleep quality\u003csup\u003e[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e, others report null findings, particularly for interventions conducted outside the evening window\u003csup\u003e[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e. This inconsistency underscores the complex, multifaceted nature of sleep regulation, which can be influenced by activity timing, intensity, baseline sleep hygiene, and powerful confounding factors such as evening screen time and family routines\u003csup\u003e[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e. The relationship between structured afternoon PA and objectively measured sleep parameters in Chinese children, who often face significant academic pressure, is therefore an open and pertinent question.\u003c/p\u003e\u003cp\u003eOn the basis of this context, this study conducted a comprehensive evaluation of the 12-week after-school program\u0026rsquo;s effects on a set of outcomes: body composition, physical fitness, agility, habitual PA, and sleep parameters. The aim of this study is to provide a holistic reference for optimizing after-school service programs and understanding their multifaceted impact on children\u0026rsquo;s health.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"2. Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1. Subjects\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThis study employed a nonrandomized quasi-experimental design and was conducted at a primary school in Mentougou District, Beijing, from September to December 2024. Fourth-grade students served as the research subjects and were divided into an experimental group and a control group on the basis of their willingness to participate. All participants were free of contraindications to exercise or severe chronic diseases. The sample size was calculated via G-Power 3.1.9.7 software on the basis of the primary outcome of physical fitness; repeated-measures ANOVA interaction effects with an effect size of f\u0026thinsp;=\u0026thinsp;0.25, α\u0026thinsp;=\u0026thinsp;0.05 (two-tailed), and statistical power (1-β)\u0026thinsp;=\u0026thinsp;0.8 were selected. The calculated sample size was n\u0026thinsp;=\u0026thinsp;28 (14 per group). The study ultimately enrolled 34 students: 18 in the experimental group (7 males, 11 females) and 16 in the control group (7 males, 9 females), meeting the sample size requirements.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2. Methods\u003c/h2\u003e\u003cdiv id=\"Sec5\" class=\"Section3\"\u003e\u003ch2\u003e2.2.1. After-School Physical Activity Program\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe after-school physical activity program was designed in accordance with the spirit of the \u0026ldquo;Guiding Opinions of the General Office of the Ministry of Education on Doing a Good Job in After-school Services for Primary and Secondary School Students\u0026rdquo;\u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e and was tailored to the physical and mental development characteristics of fourth-grade students. The experimental group participated in a 12-week structured physical activity program consisting of 5 sessions per week, each lasting 40 minutes. The programme encompassed modules including aerobic exercise, strength training, flexibility, and agility (details in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). The control group engaged in self-supervised free activities after school. These free activities were unstructured and took place in common school areas such as classrooms, libraries, or playgrounds. Students were permitted to choose rest, quiet study, social interaction, or light physical play at their own discretion under the general supervision of school staff for safety and order. The research team did not monitor or record the daily activities of this group; instead, group differences were compared solely through post-intervention physical fitness tests, thereby ensuring the validity of the comparison with the experimental group that received the structured exercise intervention.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eArrangement of the after-school physical activity program for primary school students\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSession Arrangement\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eContents\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSessions/Week\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eDuration (min)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eIntensity (% of\u003c/p\u003e\u003cp\u003eMax HeartRate)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWarm-up\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eJogging/Joint Preparation/Warm-up Games\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026mdash;\u0026mdash;\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAerobic/Strength/Flexibility Training\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eRelay Run/Endurance Run/Rope Skipping/Dribble Relay/Maximum Stretch/Squat Jump/Superman Exercise/Plank, etc.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e60%~80%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAgility Training\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eW-shaped/T-shaped/Z-shaped/Y-shaped/Cross/Fan/Triangle Direction Change Run/Agility Ladder Steps\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e60%~70%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCool-down\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCool-down Exercises\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e\u0026mdash;\u0026mdash;\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec6\" class=\"Section3\"\u003e\u003ch2\u003e2.2.2. Body composition indicator measurement and classification standards\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eBody composition indicators included weight, body mass index (BMI), waist circumference, hip circumference, waist‒hip ratio, and body fat percentage. Height, weight, waist circumference, and hip circumference are measured by professionals, whereas body fat percentage is assessed via a body composition analyzer (Sihai Huachen, Shanghai). BMI\u0026thinsp;=\u0026thinsp;weight (kg)/height\u0026sup2; (m\u0026sup2;), WHR\u0026thinsp;=\u0026thinsp;waist circumference (cm)/hip circumference (cm). Overweight and obesity in children and adolescents are defined via the \u0026ldquo;Chinese BMI Screening and Classification Standards for Overweight and Obesity in Children and Adolescents\u0026rdquo;\u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec7\" class=\"Section3\"\u003e\u003ch2\u003e2.2.3. Physical Fitness Indicator Measurement\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThese include 1-minute sit-ups, 1-minute rope skipping, sit-and-reach, standing long jump, 50 m sprint, and 50 m\u0026times;8 shuttle runs. All indicators were tested according to the National Student Physical Health Standard (Revised 2014)\u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec8\" class=\"Section3\"\u003e\u003ch2\u003e2.2.4. Agility Indicator Measurement\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe tests included the t-test, Illinois agility test, 15-s burpee test, 15-s four-square jump test, 5-0-5 agility test, hexagon jump test, and hexagon reaction ball test. Each indicator was determined through a literature review and expert consultation.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec9\" class=\"Section3\"\u003e\u003ch2\u003e2.2.5. Physical Activity and Sleep Assessment\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe Actigraph GT3X accelerometer (worn on the right hip) measured participants\u0026rsquo; physical activity and sedentary and sleep behavior over 7 days (including 5 school days\u0026thinsp;+\u0026thinsp;2 weekend days), which were removed only during aquatic activities. The data were collected from 00:00 on the distribution day until the device returned on day 8, with 10-second sampling intervals. The data were analyzed via ActLife 6.5 software. The valid wear time was screened on the basis of Choi\u0026rsquo;s criteria\u003csup\u003e[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e, and activity levels were categorized according to the intensity thresholds proposed by Zhu et al.\u003csup\u003e[\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]\u003c/sup\u003e Chinese children and adolescents engaged in sedentary behavior (SB), low-intensity physical activity (LPA), moderate-intensity physical activity (MPA), and vigorous-intensity physical activity (VPA), with cutoff points of 100, 2800, and 4000 counts per minute, respectively. (VPA). Moderate-to-vigorous physical activity (MVPA)\u0026thinsp;=\u0026thinsp;moderate physical activity (MPA)\u0026thinsp;+\u0026thinsp;vigorous physical activity (VPA). All analyses excluded data from after-school sports service periods. Sleep data processing employs the Sedah algorithm\u003csup\u003e[\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]\u003c/sup\u003e, which is suitable for pediatric and adolescent sleep. It primarily utilizes accelerometer data collected at 60-second intervals and a fully automated algorithm validated against 24-hour waist\u0026ndash;worn accelerometer measurements. Selected metrics from the measured data\u0026mdash;including sleep onset time, sleep offset time, sleep period, sleep efficiency, wake after sleep onset (WASO), number of arousals, and average awaking time\u0026mdash;serve as the sleep parameters for analysis in children and adolescents.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec10\" class=\"Section3\"\u003e\u003ch2\u003e2.2.6. Data collection\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThis study conducted three data collection sessions in September (baseline), November (midterm), and December (endterm) 2024. The specific testing schedule was as follows: body composition was assessed in September and December (pre- and post-intervention); physical fitness, agility, physical activity levels (experimental group), and sleep (experimental group) were measured at all three time points. This approach balanced data completeness with economic conditions (e.g., minimizing invasive blood draws). The detailed collection protocols are outlined in Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSchedule of Data Collection for Each Indicator\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCategory of Indicators\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSpecific indicators\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eTesting Time Points for the Experimental Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eTesting Time Points for the Control Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eNotes\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eBody Composition\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eBody Weight, BMI, Body Fat Percentage, etc.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSep, Dec\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSep, Dec\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eBody composition metrics change slowly, with only pre- and postmeasurements conducted.\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePhysical Fitness and Agility\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e50-m sprint, T-test, etc.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSep, Nov, Dec\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSep, Nov, Dec\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eMeasured at three time points to monitor dynamic changes in physical performance.\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePhysical Activity and Sleep\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMVPA, SB, sleep period, etc. (ActiGraph GT3X)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSep, Nov, Dec\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e---\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eAccelerometers are expensive, and only the experimental group wore them.\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec11\" class=\"Section3\"\u003e\u003ch2\u003e2.2.7. Quality Control\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eService protocols are designed and implemented by the Sports Medicine and Physical Education team at Beijing Sport University to ensure service quality and safety. All the researchers underwent standardized training before conducting testing and data collection. The impact of dietary confounding factors is minimized through home health education (the distribution of advocacy materials and nutrition manuals). Data undergo dual entry and cross-verification to ensure accuracy.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec12\" class=\"Section3\"\u003e\u003ch2\u003e2.2.8. Statistical methods\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eData analysis was performed via SPSS 26.0. Continuous variables were assessed for normality via the Shapiro‒Wilk test. Data are presented as the mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation (SD) for normally distributed variables and were compared via the independent samples t-test; nonnormally distributed variables are expressed as the median (interquartile range, IQR) and were compared via the Mann‒Whitney U test. Changes in body composition, physical fitness, and agility indicators between the two groups of elementary school students were compared via two-way repeated-measures ANOVA. When interaction effects were present, simple effects analysis was performed. Changes in physical activity and sleep indicators within the experimental group were compared via one-way repeated-measures ANOVA. A \u003cem\u003eP\u003c/em\u003e value\u0026thinsp;\u0026lt;\u0026thinsp;0.05 was considered statistically significant.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\u003ch2\u003e3.1. Baseline characteristics\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThere were no statistically significant differences in baseline body composition, physical fitness, or agility indicators between the two groups of students (Tables\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, \u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, \u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e) (all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05), indicating comparability at the start of the intervention.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of body composition indicators at baseline among primary school students in the two groups (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\stackrel{-}{x}\\)\u003c/span\u003e\u003c/span\u003e\u0026plusmn;s)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"9\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eHeight (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eWeight (kg)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eBMI/(kg*m\u003csup\u003e\u0026minus;\u0026thinsp;2)\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eBody fat (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eWaist circumference (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eHip circumference (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eWaist-to-hip ratio\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e143.06\u0026thinsp;\u0026plusmn;\u0026thinsp;8.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e34.65(28.25\u0026thinsp;~\u0026thinsp;46.65)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e17.03(15.06\u0026thinsp;~\u0026thinsp;20.47)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e22.21\u0026thinsp;\u0026plusmn;\u0026thinsp;9.38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e57.00(52.98\u0026thinsp;~\u0026thinsp;72.58)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e77.26\u0026thinsp;\u0026plusmn;\u0026thinsp;9.90\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.81\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e139.61\u0026thinsp;\u0026plusmn;\u0026thinsp;7.55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e33.25(29.20\u0026thinsp;~\u0026thinsp;47.65)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e18.19(15.16\u0026thinsp;~\u0026thinsp;24.42)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e26.99\u0026thinsp;\u0026plusmn;\u0026thinsp;12.29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e65.15(56.07\u0026thinsp;~\u0026thinsp;77.10)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e80.31\u0026thinsp;\u0026plusmn;\u0026thinsp;12.05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.85\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003et/z\u003c/em\u003e value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.253\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e-0.053\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e-0.752\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-1.264\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e-0.840\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e-0.801\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e-1.496\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.219\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.958\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c5\"\u003e\u003cp\u003e0.452\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.215\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.401\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.429\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.144\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"9\"\u003eNote: Data are presented as the means\u0026thinsp;\u0026plusmn;\u0026thinsp;SDs or medians (IQRs); p values were obtained from independent samples t tests (normally distributed data) or Mann‒Whitney U tests (nonnormally distributed data).\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of physical fitness indicators at baseline among primary school students in the two groups (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\stackrel{-}{x}\\)\u003c/span\u003e\u003c/span\u003e\u0026plusmn;s)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"8\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003en\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1-min sit-ups (reps)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e50 m sprint (s)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e1-min rope skipping (reps)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eSit-and-reach (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eStanding long jump (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003e50 m\u0026times;8 shuttle run (s)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e34.56\u0026thinsp;\u0026plusmn;\u0026thinsp;11.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e10.51(10.13\u0026thinsp;~\u0026thinsp;11.71)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e145.38\u0026thinsp;\u0026plusmn;\u0026thinsp;31.48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e12.21\u0026thinsp;\u0026plusmn;\u0026thinsp;5.27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e148.00\u0026thinsp;\u0026plusmn;\u0026thinsp;21.27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e134.02(115.06\u0026thinsp;~\u0026thinsp;155.71)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e33.22\u0026thinsp;\u0026plusmn;\u0026thinsp;13.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e10.74(10.03\u0026thinsp;~\u0026thinsp;11.82)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e138.56\u0026thinsp;\u0026plusmn;\u0026thinsp;30.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e14.16\u0026thinsp;\u0026plusmn;\u0026thinsp;6.31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e141.56\u0026thinsp;\u0026plusmn;\u0026thinsp;16.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e132.37(124.80\u0026thinsp;~\u0026thinsp;147.29)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003et/z\u003c/em\u003e value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.306\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e-0.069\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.646\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-0.970\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e1.003\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e-0.276\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.761\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.945\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.523\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.339\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.323\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.783\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"8\"\u003eNote: Data are presented as the means\u0026thinsp;\u0026plusmn;\u0026thinsp;SDs or medians (IQRs); p values were obtained from independent samples t tests (normally distributed data) or Mann‒Whitney U tests (nonnormally distributed data).\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of agility indicators at baseline among primary school students in the two groups (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\stackrel{-}{x}\\)\u003c/span\u003e\u003c/span\u003e\u0026plusmn;s)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"9\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eT test (s)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eIllinois agility run (s)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e15-s Burpee (reps)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e15-s Four- Square Jump (reps)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003e5-0-5 Agility Test (s)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eHexagon Jump (s)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eHexagon Reaction Ball Test (s)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e17.37\u0026thinsp;\u0026plusmn;\u0026thinsp;2.54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e20.41\u0026thinsp;\u0026plusmn;\u0026thinsp;1.16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e8.44\u0026thinsp;\u0026plusmn;\u0026thinsp;1.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e30.25\u0026thinsp;\u0026plusmn;\u0026thinsp;8.91\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e3.06(2.96\u0026thinsp;~\u0026thinsp;3.17)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e16.52(15.43\u0026thinsp;~\u0026thinsp;18.12)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e1.08\u0026thinsp;\u0026plusmn;\u0026thinsp;0.44\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEG\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e18.04\u0026thinsp;\u0026plusmn;\u0026thinsp;3.06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e20.67\u0026thinsp;\u0026plusmn;\u0026thinsp;1.66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e8.00\u0026thinsp;\u0026plusmn;\u0026thinsp;1.28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e24.89\u0026thinsp;\u0026plusmn;\u0026thinsp;8.09\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e3.10(2.91\u0026thinsp;~\u0026thinsp;3.30)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e18.35(17.00\u0026thinsp;~\u0026thinsp;18.93)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e1.24\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003et/z\u003c/em\u003e value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.685\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.504\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-1.040\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e-1.839\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e-0.385\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e-1.855\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e1.124\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.499\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.618\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.306\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.075\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e0.700\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c8\"\u003e\u003cp\u003e0.064\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.269\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"9\"\u003eNote: Data are presented as the means\u0026thinsp;\u0026plusmn;\u0026thinsp;SDs or medians (IQRs); p values were obtained from independent samples t tests (normally distributed data) or Mann‒Whitney U tests (nonnormally distributed data).\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\u003ch2\u003e3.2. Effects on Body Composition\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe results indicate that the main effects of time on height, weight, BMI, body fat percentage, hip circumference, and waist‒to-hip ratio were statistically significant, with post-test values higher than pre-test values for all indicators; the interaction effects for weight and waist circumference were statistically significant (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;101.625, 67.577, 31.849, 9.545, 16.902, 9.932, 4.551, 4.996; all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), whereas the main effects of group were not statistically significant. Further simple effect analysis revealed no significant changes in post-test body fat percentage or hip circumference in the experimental group compared with the pre-test group (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3.489, 3.856; both \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05), whereas both measures significantly increased in the control group (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;6.175, 14.431; both \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05); the waist‒hip ratio in the experimental group decreased significantly at post-test compared with pre-test (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;12.290, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01), whereas no significant change was detected in the control group (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;1.053, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05). (Table\u0026nbsp;\u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e).\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of body composition indicators between primary school students in the two groups before and after the intervention (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\stackrel{-}{x}\\)\u003c/span\u003e\u003c/span\u003e\u0026plusmn;s)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"10\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTest time\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHeight (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eWeight (kg)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eBMI/(kg*m\u003csup\u003e\u0026minus;\u0026thinsp;2)\u003c/sup\u003e\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eBody fat (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eWaist circumference (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eHip circumference (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c10\"\u003e\u003cp\u003eWaist-to-hip ratio\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePre\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e143.06\u0026thinsp;\u0026plusmn;\u0026thinsp;8.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e37.76\u0026thinsp;\u0026plusmn;\u0026thinsp;12.44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e18.09\u0026thinsp;\u0026plusmn;\u0026thinsp;4.22\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e22.21\u0026thinsp;\u0026plusmn;\u0026thinsp;9.38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e63.12\u0026thinsp;\u0026plusmn;\u0026thinsp;11.96\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e77.26\u0026thinsp;\u0026plusmn;\u0026thinsp;9.90\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.81\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePost\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e144.63\u0026thinsp;\u0026plusmn;\u0026thinsp;8.76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e40.21\u0026thinsp;\u0026plusmn;\u0026thinsp;13.37\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e18.84\u0026thinsp;\u0026plusmn;\u0026thinsp;4.43\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e23.59\u0026thinsp;\u0026plusmn;\u0026thinsp;9.61\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e64.11\u0026thinsp;\u0026plusmn;\u0026thinsp;11.96\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e79.46\u0026thinsp;\u0026plusmn;\u0026thinsp;9.85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.80\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExperimental\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePre\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e139.61\u0026thinsp;\u0026plusmn;\u0026thinsp;7.55\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e40.91\u0026thinsp;\u0026plusmn;\u0026thinsp;15.19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e20.61\u0026thinsp;\u0026plusmn;\u0026thinsp;6.01\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e26.99\u0026thinsp;\u0026plusmn;\u0026thinsp;12.29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e68.54\u0026thinsp;\u0026plusmn;\u0026thinsp;14.73\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e80.31\u0026thinsp;\u0026plusmn;\u0026thinsp;12.05\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.85\u0026thinsp;\u0026plusmn;\u0026thinsp;0.07\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePost\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e141.00\u0026thinsp;\u0026plusmn;\u0026thinsp;7.84\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e42.46\u0026thinsp;\u0026plusmn;\u0026thinsp;15.27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e20.99\u0026thinsp;\u0026plusmn;\u0026thinsp;5.82\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e27.98\u0026thinsp;\u0026plusmn;\u0026thinsp;10.80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e66.93\u0026thinsp;\u0026plusmn;\u0026thinsp;15.63\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e81.38\u0026thinsp;\u0026plusmn;\u0026thinsp;10.99\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.81\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003csub\u003e1\u003c/sub\u003e-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.004\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.600\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.004\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003csub\u003e2\u003c/sub\u003e-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.214\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.583\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.203\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.217\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.387\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.504\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.356\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.544\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.041\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.069\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.602\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.033\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.166\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.107\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"10\"\u003eNote: \u003cem\u003eP\u003c/em\u003e\u003csub\u003e1\u003c/sub\u003e indicates the main effect of time, \u003cem\u003eP\u003c/em\u003e\u003csub\u003e2\u003c/sub\u003e indicates the main effect of group, and \u003cem\u003eP\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e indicates the interaction effect.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\u003ch2\u003e3.3. Effects on physical fitness\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe results indicate statistically significant interaction effects for the 1-min sit-ups, 50-m sprint, sit-and-reach, and 50 m \u0026times; 8 shuttle run tests (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;5.052, 3.594, 6.641, 4.026; all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The main effects of time on the 1-min sit-ups and sit-and-reach test results were statistically significant (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;6.504, 3.103; both \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Further simple effect analysis revealed that the experimental group demonstrated superior mid-test and post-test results compared with the pre-test results for both the 1-min sit-ups and sit-and-reach groups (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;11.001, 6.992; both \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01), with post-test sit-and-reach scores significantly exceeding those of the control group (mean difference: 5.736\u0026thinsp;\u0026plusmn;\u0026thinsp;1.721 cm, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01). The experimental group\u0026rsquo;s post-test results for 1-min rope skipping were superior to the pre-test results, whereas the mid-test results for the 50 m\u0026times;8 shuttle run were better than the pre-test results. Additionally, the post-test results for the 50-m sprint group outperformed those of the control group (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;3.088, 4.119, 3.559; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.053, 0.062, 0.068). Although these results did not reach statistical significance, the \u003cem\u003eP\u003c/em\u003e values approached 0.05, suggesting that these effects may have potential statistical significance. (Table\u0026nbsp;\u003cspan refid=\"Tab7\" class=\"InternalRef\"\u003e7\u003c/span\u003e).\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab7\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 7\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of physical fitness indicators of primary school students between the two groups on the pre-, mid-, and post-test (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\stackrel{-}{x}\\)\u003c/span\u003e\u003c/span\u003e\u0026plusmn;s)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"9\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTest time\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1-min sit-ups (reps)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003e50 m sprint (s)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e1-min rope skipping (reps)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eSit-and-reach (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eStanding long jump (cm)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003e50 m\u0026times;8 shuttle run (s)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePre\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e34.56\u0026thinsp;\u0026plusmn;\u0026thinsp;11.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e10.89\u0026thinsp;\u0026plusmn;\u0026thinsp;1.34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e145.38\u0026thinsp;\u0026plusmn;\u0026thinsp;31.48\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e12.21\u0026thinsp;\u0026plusmn;\u0026thinsp;5.27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e148.00\u0026thinsp;\u0026plusmn;\u0026thinsp;21.27\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e135.94\u0026thinsp;\u0026plusmn;\u0026thinsp;21.09\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMid\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e34.13\u0026thinsp;\u0026plusmn;\u0026thinsp;10.89\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e11.36\u0026thinsp;\u0026plusmn;\u0026thinsp;1.51\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e149.81\u0026thinsp;\u0026plusmn;\u0026thinsp;33.98\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e10.33\u0026thinsp;\u0026plusmn;\u0026thinsp;4.82\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e151.19\u0026thinsp;\u0026plusmn;\u0026thinsp;19.53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e135.43\u0026thinsp;\u0026plusmn;\u0026thinsp;21.57\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePost\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e36.88\u0026thinsp;\u0026plusmn;\u0026thinsp;11.92\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e12.34\u0026thinsp;\u0026plusmn;\u0026thinsp;1.06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e146.19\u0026thinsp;\u0026plusmn;\u0026thinsp;28.80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e9.78\u0026thinsp;\u0026plusmn;\u0026thinsp;4.50\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e147.44\u0026thinsp;\u0026plusmn;\u0026thinsp;16.82\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e140.26\u0026thinsp;\u0026plusmn;\u0026thinsp;19.36\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eExperimental\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePre\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e33.22\u0026thinsp;\u0026plusmn;\u0026thinsp;13.17\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e13.83\u0026thinsp;\u0026plusmn;\u0026thinsp;9.66\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e138.56\u0026thinsp;\u0026plusmn;\u0026thinsp;30.04\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e14.16\u0026thinsp;\u0026plusmn;\u0026thinsp;6.31\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e141.56\u0026thinsp;\u0026plusmn;\u0026thinsp;16.10\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e137.58\u0026thinsp;\u0026plusmn;\u0026thinsp;20.93\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMid\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e38.00\u0026thinsp;\u0026plusmn;\u0026thinsp;11.60\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e11.22\u0026thinsp;\u0026plusmn;\u0026thinsp;1.88\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e146.06\u0026thinsp;\u0026plusmn;\u0026thinsp;25.58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e13.38\u0026thinsp;\u0026plusmn;\u0026thinsp;6.13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e144.72\u0026thinsp;\u0026plusmn;\u0026thinsp;15.92\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e145.42\u0026thinsp;\u0026plusmn;\u0026thinsp;35.97\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePost\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e38.50\u0026thinsp;\u0026plusmn;\u0026thinsp;9.67\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e11.10\u0026thinsp;\u0026plusmn;\u0026thinsp;2.44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e155.44\u0026thinsp;\u0026plusmn;\u0026thinsp;34.83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e15.51\u0026thinsp;\u0026plusmn;\u0026thinsp;5.42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e144.72\u0026thinsp;\u0026plusmn;\u0026thinsp;14.82\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e140.11\u0026thinsp;\u0026plusmn;\u0026thinsp;38.13\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003csub\u003e1\u003c/sub\u003e-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.004\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.384\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.122\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.008\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.294\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.319\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003csub\u003e2\u003c/sub\u003e-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.715\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.593\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.964\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.053\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.352\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.676\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.013\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.035\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.173\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.002\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.568\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.028\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"9\"\u003eNote: \u003cem\u003eP\u003c/em\u003e\u003csub\u003e1\u003c/sub\u003e indicates the main effect of time, \u003cem\u003eP\u003c/em\u003e\u003csub\u003e2\u003c/sub\u003e indicates the main effect of group, and \u003cem\u003eP\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e indicates the interaction effect.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\u003ch2\u003e3.4. Effects on Agility\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe results indicate that the interaction effects for the 15-s burpee, 15-s four-square, and hexagon jumps were statistically significant (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;10.286, 4.564, and 6.368; all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The main effects of time for the t-test, Illinois agility run, 15-s burpee, 15-s four-square jump, 5-0-5 agility test, and hexagon jump were statistically significant (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;10.167, 4.186, 26.228, 85.831, 9.310, 38.100; all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The main effects of group on the 15-s burpee and hexagon reaction ball tests were statistically significant (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;4.445, 6.028; both \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Further simple effects analysis revealed that the experimental group demonstrated superior mid-test and post-test scores compared with pre-test scores in the T-test, 15-s burpee, 15-s four-square jump, and hexagonal jump (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;7.262, 39.194, 51.245, 38.331; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Moreover, the experimental group demonstrated superior mid-test performance compared with the control group in the 15-s burpee, hexagon jump, and hexagonal reaction ball tests (mean differences: 2.028\u0026thinsp;\u0026plusmn;\u0026thinsp;0.577 reps, -0.142\u0026thinsp;\u0026plusmn;\u0026thinsp;0.633 s, and \u0026minus;\u0026thinsp;0.202\u0026thinsp;\u0026plusmn;\u0026thinsp;0.099 s; \u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;12.369, 4.969, and 4.093; all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). The post-test results for the 5-0-5 agility test in the experimental group were superior to those of the control group (mean difference: 0.187\u0026thinsp;\u0026plusmn;\u0026thinsp;0.086 s; \u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;4.749; \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). (Table\u0026nbsp;\u003cspan refid=\"Tab8\" class=\"InternalRef\"\u003e8\u003c/span\u003e).\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab8\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 8\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of sensitivity indicators of primary school students between the two groups on the pre-, mid-, and post-test (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\stackrel{-}{x}\\)\u003c/span\u003e\u003c/span\u003e\u0026plusmn;s)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"10\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTest time\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eT-test (s)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eIllinois Agility Run (s)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003e15-s Burpee (reps)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003e15-s four-square jump (reps)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003e5-0-5 Agility test (s)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eHexagon jump (s)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c10\"\u003e\u003cp\u003eHexagon Reaction Ball Test (s)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eControl\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePre\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e17.37\u0026thinsp;\u0026plusmn;\u0026thinsp;2.54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20.48\u0026thinsp;\u0026plusmn;\u0026thinsp;1.16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e8.44\u0026thinsp;\u0026plusmn;\u0026thinsp;1.15\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e30.25\u0026thinsp;\u0026plusmn;\u0026thinsp;8.91\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e3.07\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e17.09\u0026thinsp;\u0026plusmn;\u0026thinsp;2.46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e1.08\u0026thinsp;\u0026plusmn;\u0026thinsp;0.44\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMid\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e16.56\u0026thinsp;\u0026plusmn;\u0026thinsp;2.06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e19.81\u0026thinsp;\u0026plusmn;\u0026thinsp;1.20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e8.75\u0026thinsp;\u0026plusmn;\u0026thinsp;0.93\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e39.50\u0026thinsp;\u0026plusmn;\u0026thinsp;7.80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e2.99\u0026thinsp;\u0026plusmn;\u0026thinsp;0.19\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e16.06\u0026thinsp;\u0026plusmn;\u0026thinsp;2.44\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.96\u0026thinsp;\u0026plusmn;\u0026thinsp;0.39\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePost\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e16\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e17.44\u0026thinsp;\u0026plusmn;\u0026thinsp;1.85\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20.34\u0026thinsp;\u0026plusmn;\u0026thinsp;1.23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e9.56\u0026thinsp;\u0026plusmn;\u0026thinsp;1.09\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e40.25\u0026thinsp;\u0026plusmn;\u0026thinsp;6.39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e3.28\u0026thinsp;\u0026plusmn;\u0026thinsp;0.29\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e15.08\u0026thinsp;\u0026plusmn;\u0026thinsp;3.30\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.98\u0026thinsp;\u0026plusmn;\u0026thinsp;0.33\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eExperimental\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePre\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e18.04\u0026thinsp;\u0026plusmn;\u0026thinsp;3.06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20.58\u0026thinsp;\u0026plusmn;\u0026thinsp;1.64\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e8.00\u0026thinsp;\u0026plusmn;\u0026thinsp;1.28\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e24.89\u0026thinsp;\u0026plusmn;\u0026thinsp;8.09\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e3.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e18.77\u0026thinsp;\u0026plusmn;\u0026thinsp;2.80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e1.24\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMid\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e15.89\u0026thinsp;\u0026plusmn;\u0026thinsp;1.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20.20\u0026thinsp;\u0026plusmn;\u0026thinsp;1.53\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e10.78\u0026thinsp;\u0026plusmn;\u0026thinsp;2.13\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e39.33\u0026thinsp;\u0026plusmn;\u0026thinsp;4.07\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e3.06\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e14.65\u0026thinsp;\u0026plusmn;\u0026thinsp;1.06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e1.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.13\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePost\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e16.34\u0026thinsp;\u0026plusmn;\u0026thinsp;1.65\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e20.02\u0026thinsp;\u0026plusmn;\u0026thinsp;1.32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e10.56\u0026thinsp;\u0026plusmn;\u0026thinsp;1.88\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e41.11\u0026thinsp;\u0026plusmn;\u0026thinsp;5.40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e3.10\u0026thinsp;\u0026plusmn;\u0026thinsp;0.18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e14.20\u0026thinsp;\u0026plusmn;\u0026thinsp;1.61\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e1.03\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003csub\u003e1\u003c/sub\u003e-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.020\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.001\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.212\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003csub\u003e2\u003c/sub\u003e-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.574\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.887\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.012\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.441\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.138\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.762\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.035\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e-value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.091\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.164\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.203\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.027\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.473\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"10\"\u003eNote: \u003cem\u003eP\u003c/em\u003e\u003csub\u003e1\u003c/sub\u003e indicates the main effect of time, \u003cem\u003eP\u003c/em\u003e\u003csub\u003e2\u003c/sub\u003e indicates the main effect of group, and \u003cem\u003eP\u003c/em\u003e\u003csub\u003e3\u003c/sub\u003e indicates the interaction effect.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\u003ch2\u003e3.5. Effects on the physical activity levels of the experimental groups\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eEleven participants in the experimental group completed physical activity monitoring. After excluding after-school sports service periods, both their daily moderate-intensity physical activity (MPA) and moderate-to-vigorous physical activity (MVPA) times significantly improved (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;26.178, 8.270; both \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01). The MPA levels at both the mid-test and post-test were greater than those at the pretest, with the MPA level at the mid-test exceeding that at the post-test (both P\u0026thinsp;\u0026lt;\u0026thinsp;0.05); the MPA level at the mid-test was greater than that at the pre-test (\u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). However, no significant changes were observed in sedentary behavior (SB), low-intensity physical activity (LPA), or vigorous-intensity physical activity (VPA) duration (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;4.721, 0.097, 0.681; all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05), as shown in Table\u0026nbsp;\u003cspan refid=\"Tab9\" class=\"InternalRef\"\u003e9\u003c/span\u003e.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab9\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 9\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of physical activity indicators of primary school students in the experimental group on the pre-, mid-, and post-test (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\stackrel{-}{x}\\)\u003c/span\u003e\u003c/span\u003e\u0026plusmn;s)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"8\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTest time\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSB (min/day)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eLPA (min/day)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eMPA (min/day)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eVPA (min/day)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eMVPA (min/day)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eExperimental\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePre\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e413.26\u0026thinsp;\u0026plusmn;\u0026thinsp;89.03\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e436.42\u0026thinsp;\u0026plusmn;\u0026thinsp;42.40\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e16.82\u0026thinsp;\u0026plusmn;\u0026thinsp;5.75\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e13.38\u0026thinsp;\u0026plusmn;\u0026thinsp;7.81\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e30.20\u0026thinsp;\u0026plusmn;\u0026thinsp;11.97\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMid\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e394.48\u0026thinsp;\u0026plusmn;\u0026thinsp;94.23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e432.16\u0026thinsp;\u0026plusmn;\u0026thinsp;47.46\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e27.32\u0026thinsp;\u0026plusmn;\u0026thinsp;7.97\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e12.56\u0026thinsp;\u0026plusmn;\u0026thinsp;5.54\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e39.88\u0026thinsp;\u0026plusmn;\u0026thinsp;12.21\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePost\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e11\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e441.52\u0026thinsp;\u0026plusmn;\u0026thinsp;78.76\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e438.97\u0026thinsp;\u0026plusmn;\u0026thinsp;51.00\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e21.79\u0026thinsp;\u0026plusmn;\u0026thinsp;7.66\u003csup\u003eab\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e11.54\u0026thinsp;\u0026plusmn;\u0026thinsp;5.39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e33.33\u0026thinsp;\u0026plusmn;\u0026thinsp;11.65\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.089\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.899\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.000\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.509\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.003\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"8\"\u003eNote: SB: sedentary behavior; LPA: light physical activity; MPA: moderate physical activity; VPA: vigorous physical activity; MVPA: moderate to vigorous physical activity. \u0026lt;sup\u0026thinsp;\u0026gt;\u0026thinsp;a\u0026lt;/sup\u0026thinsp;\u0026gt;\u0026thinsp;Significantly different from baseline, P\u0026thinsp;\u0026lt;\u0026thinsp;0.05; \u0026lt;sup\u0026thinsp;\u0026gt;\u0026thinsp;b\u0026lt;/sup\u0026thinsp;\u0026gt;\u0026thinsp;significantly different from the middle test, P\u0026thinsp;\u0026lt;\u0026thinsp;0.05. All pairwise comparisons were adjusted via the Bonferroni correction.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec19\" class=\"Section2\"\u003e\u003ch2\u003e3.6. Effects on Sleep Parameters in the Experimental Group\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eTwelve participants in the experimental group completed sleep monitoring. No significant changes were observed from baseline to post-intervention in sleep onset time, sleep offset time, sleep period, sleep efficiency, WASO, number of arousals, or average awaking time (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.828, 0.186, 0.975, 0.542, 0.625, 0.164, 1.251; all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05), as shown in Table\u0026nbsp;\u003cspan refid=\"Tab10\" class=\"InternalRef\"\u003e10\u003c/span\u003e.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab10\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 10\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eComparison of sleep indicators among primary school students in the experimental group on the pre-, mid-, and post-test (\u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\stackrel{-}{x}\\)\u003c/span\u003e\u003c/span\u003e\u0026plusmn;s)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"10\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eGroup\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eTest time\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSleep onset time\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eSleep offset time\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eSleep period (min)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003eSleep efficiency (%)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c8\"\u003e\u003cp\u003eWASO (min)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c9\"\u003e\u003cp\u003eNumber of arousals\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c10\"\u003e\u003cp\u003eAverage awaking time (min)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eexperimental\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePre\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e22:10\u0026thinsp;\u0026plusmn;\u0026thinsp;0:32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e7:17\u0026thinsp;\u0026plusmn;\u0026thinsp;0:36\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e533.40\u0026thinsp;\u0026plusmn;\u0026thinsp;33.33\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e97.57\u0026thinsp;\u0026plusmn;\u0026thinsp;1.20\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e13.59\u0026thinsp;\u0026plusmn;\u0026thinsp;6.71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e5.49\u0026thinsp;\u0026plusmn;\u0026thinsp;2.87\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e2.33\u0026thinsp;\u0026plusmn;\u0026thinsp;1.03\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMid\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e21:58\u0026thinsp;\u0026plusmn;\u0026thinsp;0:32\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e7:14\u0026thinsp;\u0026plusmn;\u0026thinsp;0:23\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e540.71\u0026thinsp;\u0026plusmn;\u0026thinsp;43.34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e97.07\u0026thinsp;\u0026plusmn;\u0026thinsp;1.83\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e16.16\u0026thinsp;\u0026plusmn;\u0026thinsp;10.06\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e5.69\u0026thinsp;\u0026plusmn;\u0026thinsp;3.09\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e2.58\u0026thinsp;\u0026plusmn;\u0026thinsp;1.00\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePost\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e12\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e22:09\u0026thinsp;\u0026plusmn;\u0026thinsp;0:39\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e7:19\u0026thinsp;\u0026plusmn;\u0026thinsp;0:26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e535.79\u0026thinsp;\u0026plusmn;\u0026thinsp;43.99\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e97.35\u0026thinsp;\u0026plusmn;\u0026thinsp;1.86\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e14.37\u0026thinsp;\u0026plusmn;\u0026thinsp;9.80\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e6.06\u0026thinsp;\u0026plusmn;\u0026thinsp;3.67\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e2.21\u0026thinsp;\u0026plusmn;\u0026thinsp;0.59\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cem\u003eP\u003c/em\u003e value\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e0.419\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e0.815\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e0.410\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u003cp\u003e0.587\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c8\"\u003e\u003cp\u003e0.541\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c9\"\u003e\u003cp\u003e0.845\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c10\"\u003e\u003cp\u003e0.305\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"10\"\u003eNote: WASO: Wake After Sleep Onset.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cdiv id=\"Sec21\" class=\"Section2\"\u003e\u003ch2\u003e4.1 The After-School PA Program Improved Primary School Students\u0026rsquo; Body Composition\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe prevalence of overweight and obesity in children and adolescents has become a major public health concern in recent decades\u003csup\u003e[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]\u003c/sup\u003e. The results of the body composition test performed in our study also indicate that the EG maintained a stable body fat percentage and hip circumference while reducing the waist‒hip ratio, whereas the CG showed increasing trends across all the metrics. These findings suggest that after-school physical activity effectively inhibits abdominal fat accumulation, which is consistent with existing research showing that exercise improves body composition\u003csup\u003e[\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e, \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]\u003c/sup\u003e. Notably, the increases in BMI and body fat percentage observed in both groups may be attributed to the following factors: 1) Children aged 9\u0026ndash;10 are in the growth and development phase, where weight and body fat gain represent normal physiological phenomena\u003csup\u003e[\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]\u003c/sup\u003e; 2) According to a systematic review by Zhu Zhiqiang et al., exercise interventions lasting over 60 minutes per session three times weekly for at least 12 weeks can significantly improve body composition in children and adolescents\u003csup\u003e[\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]\u003c/sup\u003e. The intervention period in this study may not have reached the optimal duration. 3) Increased physiological fat storage requirements during autumn and winter may also contribute to elevated body fat levels\u003csup\u003e[\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec22\" class=\"Section2\"\u003e\u003ch2\u003e4.2 The After-school PA Program Enhanced Primary School Students\u0026rsquo; Physical Fitness and Agility Ability\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eWith respect to physical fitness and agility indicators, the EG showed significant improvements in metrics such as the 50-m sprint, sit-up, sit-and-reach, and several agility ability results (t-test, etc.), indicating that after-school physical activity effectively promoted the development of multiple athletic abilities in primary school students. This result aligns with the conclusions of studies by Neil-Sztramko et al. and Zhang Bin et al.\u003csup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]\u003c/sup\u003e. However, improvements in explosive power (standing long jump) and endurance fitness (50\u0026times;8 m shuttle run) were less pronounced. One possible reason is related to testing conditions: cold, windy winter weather may have impacted performance, as previous studies indicate that cold temperatures inhibit athletic ability\u003csup\u003e[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]\u003c/sup\u003e. On the other hand, the sensitive period for strength development typically occurs between ages 10\u0026ndash;12 for girls and 12\u0026ndash;14 for boys, whereas endurance development peaks between ages 16\u0026ndash;18\u003csup\u003e[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]\u003c/sup\u003e. Fourth-grade students have not yet entered these sensitive periods, necessitating more scientifically designed training programs aligned with their developmental characteristics in the future. Nevertheless, under the \u0026ldquo;double reduction\u0026rdquo; policy, after-school sports programs remain a vital avenue to compensate for insufficient traditional physical education class time\u003csup\u003e[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e, \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]\u003c/sup\u003e. The specialized training designed in this study\u0026mdash;including aerobic, strength, and agility exercises\u0026mdash;significantly supplements standard physical education curricula. This enriches the physical education system and comprehensively enhances students\u0026rsquo; athletic capabilities.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec23\" class=\"Section2\"\u003e\u003ch2\u003e4.3 The After-School PA Program Enhanced Primary School Students\u0026rsquo; Physical Activity Levels\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eWith respect to physical activity indicators, students in the experimental group exhibited a significant increase in moderate-to-vigorous physical activity (MVPA) time outside the designated after-school sports service period. This finding indicates that after-school sports services not only directly increase structured exercise time but also, more importantly, foster the development of students\u0026rsquo; daily autonomous physical activity habits, with profound implications for promoting healthy behaviors. Second, although MVPA slightly declined after peaking at the mid-term assessment, it remained significantly higher than the baseline levels. This finding suggests that the intervention may have produced sustained behavioral changes, which is consistent with findings from previous similar studies\u003csup\u003e[\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e, \u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]\u003c/sup\u003e. The intervention program in this study achieved the core objective of the \u0026ldquo;double reduction\u0026rdquo; policy\u003csup\u003e[\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]\u003c/sup\u003e, namely, increasing students' participation time in physical activities through systematic after-school sports services.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec24\" class=\"Section2\"\u003e\u003ch2\u003e4.4 Null Effect of the After-School PA Program on Sleep Behavior\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe present study revealed no significant alterations in sleep behavior following the 12-week after-school sports service intervention, as measured by objective actigraphy metrics, including total sleep time, sleep efficiency, and the WASO. Several factors may explain the stability of the sleep parameters. First, the intervention was conducted immediately after school at 3:30 p.m. and concluded at 4:10 p.m., leaving a considerable gap between activity and bedtime. The acute effects of exercise on sleep architecture (e.g., increasing slow-wave sleep) may have dissipated at night\u003csup\u003e[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]\u003c/sup\u003e. Second, the existing sleep patterns of the participant cohort may have played a role. The baseline data indicated that the children were already obtaining close to the recommended 9\u0026ndash;11 hours of sleep per night for their age group\u003csup\u003e[\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]\u003c/sup\u003e, potentially leaving little room for significant improvement (a ceiling effect). Furthermore, the structured nature of the intervention, while beneficial for physical activity, may not have addressed the primary drivers of sleep behavior in children, which are often strongly influenced by established household routines, parental rules regarding bedtime, and screen time usage in the evenings\u003csup\u003e[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e. It is important to distinguish between the objective measures of sleep duration and efficiency reported here and potential subjective improvements in sleep quality that were not captured. The participants anecdotally reported feeling more rested, a discrepancy that suggests that actigraphy may not fully capture the perceived restorative benefits of physical activity. Future research could benefit from incorporating subjective sleep diaries or parent-reported measures to triangulate findings.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec25\" class=\"Section2\"\u003e\u003ch2\u003e4.5 Limitations and Future Perspectives\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThis study received support from multiple stakeholders, including primary schools, medical institutions, physical education universities, communities, and families. However, several practical issues emerged during implementation. First, owing to academic pressure and varying parental cooperation levels, the sample was drawn from a single grade level and was nonrandomly grouped. This may limit the generalizability of the findings and introduce selection bias. Methodologically, low accelerometer wear compliance led to high dropout rates in physical activity and sleep data, highlighting the practical difficulties of objectively monitoring physical behavior in this population. Nevertheless, the study yielded significant findings: after-school sports services effectively improved body composition (e.g., reducing the waist-to-hip ratio) and enhanced athletic qualities such as speed, strength, and agility while substantially increasing students\u0026rsquo; moderate-to-vigorous physical activity time. According to social ecology theory, individual behavior is influenced by multilevel environmental factors\u003csup\u003e[\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]\u003c/sup\u003e, with younger students\u0026rsquo; behavior being particularly dependent on family support. Future efforts should strengthen parental health education to increase their recognition of and cooperation with professional service teams. Concurrently, establishing standardized certification mechanisms for after-school sports services will promote the development of a collaborative \u0026ldquo;family-school-community\u0026rdquo; system. This comprehensive approach will increase the implementation quality and monitoring effectiveness of after-school sports services, thereby holistically advancing children\u0026rsquo;s healthy development.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"5. Conclusions","content":"\u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe 12-week structured after-school physical activity program effectively improved body composition, enhanced physical fitness and agility, and increased daily moderate-to-vigorous physical activity levels in primary school students. However, the program did not induce significant changes in objective sleep parameters. This suggests that while such programs are highly beneficial for physical health, positively impacting sleep in children who already have sufficient sleep duration may require interventions that more directly target evening routines and the home environment, in addition to providing daytime PA.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eThe following abbreviations are used in this manuscript:\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"524\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eANOVA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eAnalysis of variance\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eBMI\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eBody mass index\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eCG\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eControl Group\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eEG\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eExperimental group\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eIQR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eInterquartile range\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eLPA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eLight physical activity\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMPA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eModerate physical activity\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eMVPA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eModerate-to-vigorous physical activity\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003ePhysical activity\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003ePE\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003ePhysical education\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSB\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eSedentary behavior\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eSD\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eStandard deviation\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eVPA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eVigorous physical activity\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eWASO\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eWake after sleep onset\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003eWHR\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003eWaist-to-hip ratio\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate:\u0026nbsp;\u003c/strong\u003eWritten informed consent was obtained from all parents/guardians, and assent was obtained from all students. The protocol was approved by the Biomedical Research Ethics Committee of Peking University First Hospital (Approval No.\u003cdel cite=\"mailto:Editor%202\" datetime=\"2025-09-27T06:56\"\u003e:\u003c/del\u003e 2022 Yan 553-003-Amendment) and was conducted in accordance with the Declaration of Helsinki.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication:\u0026nbsp;\u003c/strong\u003eNot applicable. No individual data or information is provided; thus, the need for individual consent for publication is negated.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;of data and materials:\u003c/strong\u003e The datasets supporting the conclusions of this article are available in the Open Science Framework (OSF) at https://doi.org/10.17605/OSF.IO/F9EZG.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eC\u003c/strong\u003e\u003cstrong\u003eompeting\u0026nbsp;\u003c/strong\u003e\u003cstrong\u003einterest\u003c/strong\u003e\u003cstrong\u003es:\u003c/strong\u003e The authors declare that they have no conflicts of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e This research was funded by the Beijing Association of Holistic Integrative Medicine, grant number ZH-2024-2742. The APC was funded by the same grant.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor\u003c/strong\u003e\u003cstrong\u003es\u0026rsquo; Contribution\u003c/strong\u003e\u003cstrong\u003es:\u003c/strong\u003e PH and XML were responsible for the conception and design of the study. GJKH, JBY, LND and PXH were responsible for the implementation of the study. GJKH, JBY and LND managed the data collection and analysis activities. GJKH and JBY were major contributors in writing the manuscript.\u0026nbsp;GJKH and XML revised the final version of the manuscript. All authors read and approved the final manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments:\u003c/strong\u003e The authors would like to extend their sincere gratitude to all the students who participated in this study, as well as their parents and teachers\u003cins cite=\"mailto:Editor%202\" datetime=\"2025-09-27T06:56\"\u003e,\u003c/ins\u003e for their invaluable cooperation and support. The authors are also grateful for the support from\u0026nbsp;the Department of Endocrinology at Peking University First Hospital\u0026nbsp;for their essential medical assistance and support throughout this research.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026rsquo; information:\u003c/strong\u003e No additional information is necessary.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eGeneral Office of the Central Committee of the Communist Party of China, General Office of the State Council. Opinions on further reducing the burden of homework for students in compulsory education and the burden of out-of-school training B/0L]. (2021-07-24) [2023-09-19]. http: //www. gov. cn/zhengce/2021-07/24/cconten5627132.htm.( in Chinese)\u003c/li\u003e\n \u003cli\u003eYang, J.; Dai, S.T.; Yan, J.F. Construction of school physical activity and health-related curriculum in perspective of health-promoting school[J]. 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(in Chinese)\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-public-health","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"pubh","sideBox":"Learn more about [BMC Public Health](http://bmcpublichealth.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/pubh/default.aspx","title":"BMC Public Health","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"After-school programme, Body composition, Physical fitness, Physical activity, Sleep, Children","lastPublishedDoi":"10.21203/rs.3.rs-7727089/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7727089/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003ePhysical inactivity is a significant public health issue among children. While compulsory physical education (PE) may be insufficient to meet daily activity recommendations, structured after-school physical activity (PA) programs have been proposed as a complementary strategy to promote health. This study aimed to investigate the effects of a 12-week after-school PA program on body composition, physical fitness, physical activity levels, and sleep outcomes in primary school students.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eThirty-four fourth-grade students from a primary school in Beijing were nonrandomly assigned to a control group (CG, n\u0026thinsp;=\u0026thinsp;16, regular PE classes) or an experimental group (EG, n\u0026thinsp;=\u0026thinsp;18, regular PE classes plus a structured after-school PA program, 5 times/week, 40 minutes/session) on the basis of their willingness to participate. Assessments were conducted at baseline, at mid-intervention, and post-intervention. The data were analyzed via two-way repeated-measures ANOVA, t-tests, and non-parametric tests.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eBody composition: The EG significantly reduced the waist‒to‒hip ratio (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;12.290, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05) and prevented the significant increases in body fat percentage and hip circumference observed in the CG (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;6.175, 14.431, both \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05). Physical fitness and agility: The EG demonstrated significant improvements in sit-ups and sit-and-reach test results and multiple agility tests (e.g., 15-s burpee, \u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;39.194, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05), outperforming the CG in several metrics. Physical activity: Time spent in moderate-to-vigorous PA (MVPA) significantly increased in the EG (\u003cem\u003eF\u003c/em\u003e\u0026thinsp;=\u0026thinsp;8.270, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.01). Sleep: No significant within-group changes in any objective sleep parameters (e.g., sleep efficiency, total sleep time, or WASO) were observed in the EG (all \u003cem\u003eP\u003c/em\u003e\u0026thinsp;\u0026gt;\u0026thinsp;0.05).\u003c/p\u003e\u003ch2\u003eConclusion\u003c/h2\u003e\u003cp\u003eThe after-school PA program effectively improved body composition, physical fitness, and daily MVPA levels but did not significantly impact sleep, suggesting that sleep may be more influenced by household routines and baseline patterns than structured afternoon activity.\u003c/p\u003e\u003ch2\u003eTrial registration:\u003c/h2\u003e\u003cp\u003eThis study was registered prospectively in the Chinese Clinical Trial Registry (ChiCTR) on December 30, 2022 (Registration number: ChiCTR2200067241).\u003c/p\u003e","manuscriptTitle":"Effects of a Structured After-School Physical Activity Program on Physical Fitness, Body Composition, and Sleep in Primary School Students: A Quasi- Experimental 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