The Effect of Body Mass Index on Prefrontal Cortex Hemodynamic and Cognitive Functions In Exercise-Induced Hypohydration in Male Athletes

The Effect of Body Mass Index on Prefrontal Cortex Hemodynamic and Cognitive Functions In Exercise-Induced Hypohydration in Male Athletes | 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 The Effect of Body Mass Index on Prefrontal Cortex Hemodynamic and Cognitive Functions In Exercise-Induced Hypohydration in Male Athletes Cigdem Bediz, Erdem Uylas, Cagdas Guducu, Egemen Manci, Erkan Gunay This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-8820751/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 7 You are reading this latest preprint version Abstract Objectives: This study examines the impact of exercise-induced hypohydration on prefrontal hemodynamic and cognitive functions within high and low body mass index athletes. Methods: A total of twelve athletes well adapted to the bicycle ergometer were included in the study (LBMIG (24.64 kg/m²) and HBMIG (32.45 kg/m²)). Participants attended two visits to the laboratory. At their first visit, their body weight and hemocrit values were assembled, and they completed the practice 2-back test. At their second visit, participants' body weights and hematocrit values were measured, followed by recording their 2-back performance and prefrontal hemodynamic responses during performance. This session was followed by submaximal exercise and then 4x20 seconds of sprint intervals. Afterward, 2-back test performance was measured with their prefrontal hemodynamic responses. Results: Hematocrit levels increased in both groups compared to pre-exercise levels (p< 0.05), with a higher increase in the HBMIG (p=0.045). On the other hand, pre-post exercise responses in prefrontal hemodynamic activity during the 2-back test showed different patterns for each group: an increase in oxyhemoglobin for the LBMIG (p=0.002), an increase in deoxyhemoglobin for the HBMIG (p=0.033), and an increase in total hemoglobin for the HBMIG (p=0.050). Furthermore, the number of missing answers in the post-exercise 2-back test results was significantly higher in the HBMI group compared to the LBMI group. Conclusions: Exercise-induced hypohydration may negatively affects prefrontal hemodynamics and cognitive function in high-BMI athletes. This effect may cause cognitive decline in athletes with high BMI values, negatively affecting their sport or match performance under physical fatigue. Submaximal Exercise Exercise-Induced Hypohydration Prefrontal Cortex Hemodynamics Cognitive Functions BMI Figures Figure 1 Figure 2 1. Introduction Body mass index (BMI) is a critical parameter that is used to measure overall health. In the general population, a BMI value range of 18.5 to 24.9 kg/m² is considered normal, while a value range of 25 to 29.9 kg/m² is considered high BMI. A high BMI is regarded as a major contributing factor to a wide range of health concerns, primarily metabolic disorders and cardiovascular diseases. Recent studies have indicated that BMI levels may have a negative impact on brain hemodynamics [ 1 ] and cognitive performance [ 2 ]. On the other hand, for elite athletes and bodybuilders, high BMI values are associated with increased muscle mass and the resulting increase in BMI, so it is not correct to directly correlate them with overall health [ 3 ]. Athletic populations consist of individuals with a high lean body mass ratio relative to their height and typically have high BMI values [ 4 , 5 ]. However, body composition significantly influences performance in many sports. Especially in endurance-based performances, a high BMI can act as a limitation factor [ 6 ]. This limitation suggests a negative correlation between BMI and VO₂ max, implying that BMI may influence cardiovascular endurance [ 7 ]. Additionally, fluid and sodium imbalances during exercise in athletes with high BMI support this notion. This is because it is known that athletes with high BMI experience greater exercise-related fluid losses compared to those with low BMI [ 8 ]. Prolonged exercise can result in a state of dehydration. For instance, a field study of elite endurance athletes competing in international marathons revealed that body weight can decrease by 1.7% to 6.6% post-race [ 9 ]. These values are a significant indicator of the heightened physical stress experienced by athletes. The predominant factor contributing to this stress is exercise-induced hypohydration (EIH). EIH has been shown to negatively affect blood flow in microvascular circulation because there is less water in the blood and a higher concentration of hematocrit [ 10 ]. This effect has been demonstrated to have a detrimental effect on perfusion in peripheral tissues, resulting in hemodynamic deteriorations such as insufficient oxygenation and nutrition of active cells [ 11 ]. Impaired hemodynamics have the effect of reducing the amount of blood returning to the heart, which in turn increases the load on the heart [ 12 ]. The adverse effects of EIH on the cardiovascular system have been demonstrated in studies, with symptoms including increased heart rate, decreased stroke volume, and elevated blood pressure [ 13 – 15 ]. Recent research has focused on the relationship between hypohydration, brain responses, and cognitive performance [ 16 , 17 ]. Hypohydration reduces the volume of the cerebellum and thalamus, disrupts the brain's osmotic balance, but does not affect total cerebral blood volume [ 18 , 19 ]. On the other hand, a study has shown that hypohydration causes greater BOLD signal increases in brain regions associated with visual-motor tasks and learning, such as the prefrontal cortex (PFC), supplementary motor area (SMA), hippocampus, and striatum [ 20 ]. Another related study reported that hypohydration causes a temporary increase in PFC activation and that this change in blood flow affects cognitive performance Some cognitive-based studies have shown that hypohydration negatively affects cognitive processes such as information processing, decision making, problem solving, attention, memory, and motor coordination [ 21 , 22 ]. During a cognitive task, cortical tissue is activated, and changes in chromophores occur. This reveals changes in the neural system, and the responses during the task can be measured by neuroimaging devices [ 17 , 23 ]. Functional near-infrared spectroscopy (fNIRS) is a technique frequently employed to image brain hemodynamic responses [ 24 – 26 ]. This examination uses near-infrared light at different wavelengths to distinguish between oxygenated brain tissue (Oxy-Hb) and deoxygenated hemoglobin (Deoxy-Hb) tissue concentrations [ 17 , 27 ]. These changes enable the observation of oxygen consumption associated with neurovascular coupling during various tasks and conditions. Oxygen consumption in the brain provides information about the metabolic demand of a task [ 28 ]. Based on the information presented above, this study aims to investigate the differences in hemodynamic and cognitive performance of athletes with different BMI levels under EIH conditions. The hypotheses of the study are: i) Athletes with high BMI use more oxygen during cognitive tasks under EIH conditions, resulting in increased deoxyhemoglobin levels. ii) Athletes with low BMI exhibit more economical prefrontal oxygenation responses during cognitive tasks under EIH conditions. iii) Athletes with high BMI may exhibit cognitive impairments under EIH conditions compared to athletes with low BMI. We believe that this unique approach has the potential to contribute to elucidating the effects of BMI on the relationship between neurocognition and sports performance. 2. Materials and Methods 2.1. Participants Twelve healthy male competitive athletes between 18 and 29 years of age were recruited. All participants were selected from individuals who had previously participated in bicycle ergometer-based exercise tests conducted in our laboratory and were well adapted. The participants characteristics were as follows (mean ± SD): age 20.85 ± 4.0 years, training age 7.8 ± 4.2 years, body mass 97.0 ± 19.6 kg, height 184.66 ± 5.01 cm. The number of participants was calculated using the G-Power 3.1.9.4 software (Heinrich Heine University Düsseldorf, Germany) to predetermine the required sample size (T-test: Difference Between Two Dependent Means-Matched Pairs). To estimate the sample size required to determine the effects of a physical exercise session on Hemodynamic and cognitive performance in athletes, we used an effect size of f = 1.70 with an alpha (error) rate of 5% and a power of 90%. The determination in G-Power resulted in a sample size of 5 participants. Due to the overlap of the data collection process with the COVID-19 pandemic, the planned number of participants was kept at a low level. The study was planned to start with 12 participants to prevent data loss that may arise from risks during measurements and analysis results. [ 29 – 32 ]. The inclusion criteria for the study were regular training, a sports history of at least five years, and no recent lower extremity injury. Exclusion criteria were low lower limb power, injury, and irregular training. Participants were informed of the details of the test procedures, the risks involved, the measures taken, and any special instructions or risks. All participants completed the informed consent form, and their voluntary participation in the study was documented. The xxx University Non-Invasive Research Ethics Committee approved this study with the decision number 2020/07–28 dated April 13, 2020. 2.2.Study Design The research comprised two distinct sessions: a familiarisation session and an experimental intervention session. The familiarisation session spanned around 20 minutes, whereas the experimental intervention session lasted approximately 75 minutes. Throughout both the familiarisation and experimental intervention visits, participants were instructed not to engage in strenuous physical activities. All experimental sessions were executed under normothermic conditions, maintaining a temperature of 25.7 ± 0.5°C and a relative humidity of 41.3%, as indicated by the thermometer readings. Thus, there was assurance that the participants had the same hydration levels at the start of both conditions [ 32 , 33 ]. Figure 1 illustrates the applied research design for the combined familiarisation and practice sessions. The data collection process was conducted between 1 May 2020 and 1 December 2020. **** Fig. 1 Nere Here **** Figure 1. Study Design. 2.2.1.Pre-Session Standardization The participants commenced both sessions concurrently from 12 to 4 p.m. fluid consumption was ceased one hour before each session, while food intake was stopped two hours before both sessions. Furthermore, upon the participants' arrival at the laboratory before each session, inquiries were made regarding their thirst levels, their body weight was recorded, and it was confirmed that they were close to their weight during the initial session. This protocol ensured that participants initiated the exercise regimen adequately hydrated. Additionally, participants were instructed to refrain from alcohol consumption and vigorous exercise within the 24 hours preceding the two assessments. 2.2.2.Familiarisation Session All participants completed the informed consent form, and their voluntary participation in the study was documented. In the first phase, participants were informed about the experimental protocol, and demographic information was collected. Afterward, anthropometric measurements were taken. Baseline body weight (BW) and hematocrit (HCT) values were measured. Five minutes of fNIRS during the 2-back test were recorded. During this process, the teaching of the 2-step test and adaptation to the test were carried out. 2.2.3.Anthropometric Measurements The height was measured using a manual stadiometer. When participants stood upright with their backs to the stadiometer and bare feet, their height was measured by determining the top of their heads and recorded in centimeters. The body mass index (BMI) calculation was calculated using the formula below [ 33 ]. BMI = Body Weight (kg.) / Height (m) ² = kg/m² 2.2.4.Hydration Status Measurement In the study, changes in body weight and hematocrit were used to establish a constant baseline hydration status [ 33 , 34 ]. At the start of the exercise session, participants were found to have similar weight and hematocrit values to those measured at the start of the acclimatization session. In addition, feedback was obtained from the participants before the sessions that they were fully hydrated and that they were drinking fluids. Levels of hypohydration were determined by measuring both pre- and post-exercise sessions. In this assessment, BW and HCT measurements were taken together. A decrease in body weight and an increase in HCT indicate the assets of hypohydration [ 35 , 36 ]. Body weight was measured using an electronic scale. The participants stood barefoot and upright on the electronic scale until it displayed the results. The data obtained was recorded in kilograms. Hematocrit was measured before the session and at the end of the exercise. During the measurements, the participant's fingertip was pricked with a lancet, and approximately 70–80 microliters of blood (3–4 drops) were taken into two heparin tubes and filled to 2/3 of the tube. The heparinised tubes were placed in a centrifuge (Nüve NT 715), and they were centrifuged for 4 minutes at 9000–10000 rpm [ 37 ]. 2.2.5.Prefrontal Hemodynamic Measurement Participants' prefrontal hemodynamics were recorded while seated and during five minutes of cognitive testing. The Functional Near-Infrared Spectroscopy (fNIRS) system (Biopac, fNIRS DEVICES, Imager 1100, LLC, MD, USA) was used to measure changes in the blood flow in the prefrontal cortex. During the measurements, a flexible sensor pad consisting of 4 light sources with peak wavelengths of 730 nm and 850 nm and 12 detectors (4 light sources), which are 16 parts of this system, was connected to the participants' foreheads (RXFNIRA sensors real-time recording). Data was collected from 16 channels. Hemodynamic changes in cortical areas were then monitored [ 38 , 39 ]. Before recording, the forehead area was cleaned with an alcohol swab. After cleaning, the sensor pad was placed on the forehead, and the optodes were wrapped tightly around the forehead with a specially designed elastic black bandage to limit sensor pad artefacts caused by head movement [ 24 ]. The purpose of this choice was to eliminate possible ambient light and not create artefacts [ 40 , 41 ]. 2.2.6.fNIRS Data Analysis The fNIRS data were collected in blocks for the duration of the 2-back test battery. The 2-back battery of tests was carried out during the pre- and post-testing sessions. This battery lasted for approximately 4 minutes, and blocks were recorded for 120 stimulus presentations. During test processing block recording, the fNIRS system continuously collected signals from oxygenated hemoglobin (Oxy-Hb) and deoxygenated hemoglobin (Deoxy-Hb). Correct, wrong and missed answers, as well as correct and wrong reaction times, are collected in a separate cognitive data file [ 42 – 44 ]. Data collection and visualisation were performed using COBI Studio software [ 43 ]. The data obtained using COBI Studio were analysed using the fNIRSoft Pro version data collected from the 16 channels analysed. Then, the FIR filtering method (System 1200S-2 Hz) was applied to remove the general and motion-related distortions from the data. Then, considering the methods suggested by Ayaz et al., the SMAR (Applying Motion Artefact Rejection) method was applied, and the obtained data were used for statistical analysis [ 27 , 40 , 41 ]. 2.2.7.Exercise Session The exercise protocol applied attempted to simulate the loads that athletes are exposed to in real field conditions. In the study, BW and HCT measurements were taken before the exercise session, and five minutes of fNIRS were recorded during the 2-back task. Then, participants warmed up and stretched individually for five minutes. After the warm-up, participants engaged in 30 minutes of constant submaximal exercise. The Submaximal Constant-Load Cycle exercise was applied to participants in the submaximal exercise session. Before exercise, the participants' sitting height on the pre-session cycle ergometer corresponded to the iliac bone of the ergometer seat (Monark, LC6, Verberg, Sweden) [ 45 , 46 ]. After this procedure, they were asked to pedal for two minutes unloaded to adapt to the ergometer, and adaptation was achieved before the protocols. During the submaximal cycling exercise protocol, the participants performed the exercise session in both conditions by pedaling at 60 rpm/100 watts for 30 minutes. After 5 minutes of passive rest, the Sprint Interval Training (SIT) protocol was started. This protocol was chosen to elicit anaerobic performance (20 seconds - all-out). Participants performed four tests (SIT-1, SIT-2, SIT-3, SIT-4) using a bicycle ergometer (Monark LC7; Monark, Vansbro, Sweden) with active recovery (Recovery-1, Recovery-2, and Recovery-3) with a load of 100 watt/60 rpm for 2 minutes between these tests [ 47 – 49 ]. After the exercise session, all measures were repeated. 2.2.8.N-Back (2-Back) Cognition Task The 2-back cognition task is a widely used test of working memory function. This test measures the recognition and reaction time of letters placed two behind the letter index that appears on the computer screen in a mixed order [ 50 ]. For the cognitive test, participants were seated 70–90 cm from the computer screen, as suggested by Chu et al. [ 51 ]. The computer used for tests was a 13-inch Apple Macbook Air 2017 with a 1440x900 screen resolution in a 16:10 aspect ratio and a 1.8 GHz dual-core Intel Core i5 processor [ 52 ]. A 2-back test was performed on Pebl Launcher for Pebl version 2.1[ 53 ]. The test battery contains 40 target stimuli and 80 non-target stimuli. Correct, wrong and missed answers, as well as correct and wrong reaction times, are collected in a separate cognitive data file. Responses to these stimuli, including correct, wrong, and missed responses, as well as correct and wrong response times, are collected in a separate cognitive data file. Subsequently, the data obtained were analysed to evaluate the participants' executive functions under cognitive loads. The details of the test application are presented below [ 54 ]. At the beginning of each session (pre- and post-test), adaptation (familiarisation) was achieved by administering a 1-back and then a 2-back to allow participants to recognize and try out the test. To eliminate the learning effect, the test was explained to participants during a familiarisation session and then administered. The researchers administered the main part of the test. In the main part, the stimuli were presented to the participants by a series of white capital letters ("C", "H", "K", "N", "R", "W", "X", "Y") on a black background in the middle of the computer screen. Inter-stimulus interval: 1500 milliseconds (ms.), and the number of stimuli was fixed at 120. Participants pressed the left shift key on the keyboard if a letter on the screen matched the two letters behind it. The test took about 4 minutes to complete. To assess working memory performance [ 55 ], the number of correct and wrong responses to stimuli and the reaction times of these responses were recorded and analysed [ 54 , 55 ]. As a result of this test, the number of correct answers, the reaction time for correct answers, the number of wrong answers, the reaction time for wrong answers, and the number of missed answers were totalled and evaluated. 2.3.Statistical Analysis All statistical analyses were performed with a statistical package (JASP—just another statistical program, version 0.16.3). All participants were divided into two groups based on a BMI cut-off of 27. Those with a score above 27 were called HBMIG, while those below 27 were LBMIG [ 33 ]. Afterward, the Shapiro-Wilk test was applied to determine the normal distribution of data (body weight, hematocrit, oxyhemoglobin, deoxyhemoglobin, total hemoglobin, correct, wrong, missing, and reaction times). It was determined that the data were normally distributed. Before and after the exercise session was performed using a paired sample t-test. In addition, for different BMI, the paired sample t-test was used to compare the data (body weight, hematocrit, oxyhemoglobin, deoxyhemoglobin, total hemoglobin, correct, wrong, missing, and reaction times) in the high body mass index and low body mass index groups. In addition to the comparisons, the effect sizes of the data between each other were determined using the Cohen d. The statistical significance level was determined as less than 0.05 in statistical analyses (p < 0.05) [ 56 ]. 3. Results 3.1.Participants The study participants were divided into two groups: the high body mass index group (HBMIG) and the low body mass index group (LBMIG). The HBMIG had an average age of 21.33 ± 4.59 years, an average training age of 8.66 ± 4.88 years, an average height of 186.83 ± 5.03 cm, a body weight of 112.01 ± 16.25 kg, and a BMI of 32.45 ± 6.05 kg/m²; in contrast, the LBMIG consisted of 6 participants with an average age of 19.50 ± 2.07 years, a training age of 7.00 ± 3.22 years, a height of 182.50 ± 4.32 cm, a body weight of 82.06 ± 6.52 kg, and a BMI of 24.64 ± 2.02 kg/m². The average values for all groups of participants were as follows: age 20.42 ± 5.13 years; training age 8 ± 4 years; height 183.90 ± 4.48 cm; body weight 97.20 ± 4.48 kg; and BMI 25 ± 11.86 kg/m². 3.2.Hydration status-related exercise The body weight values of the HBMIG and LBMIG groups were compared before (p = 0.01) and after exercise, and a significant decrease was found (p = 0.01). Hematocrit values did not change significantly before and after exercise (p = 0.360 and p = 0.113, respectively) (see Table 1 ). Pre- and post-exercises in within-group values were examined. In terms of body weight, a significant decrease of 0.92% (p = 0.003) was observed in the HBMIG group, 0.65% (p = 0.30) in the LBMIG group, and 0.79% (p < 0.001) in all participants. In HCT values, significant increases were found in the HBMIG group (p = 0.004), LBMIG group (p = 0.002), and all groups (p < 0.001) (see Table 1 ). Table 1 The hydration level changes of the participant of within groups. Status Total Body Mass Loss (%) Liquid Intake (ml) Hydration Status (%) Pre Exercise BW (kg) Post Exercise BW (kg) p Pre Exercise HCT (%) Post Exercise HCT (%) p HBMIG -0.92 ± 0.22 0 1,031 112.13 ± 15.94 111.21 ± 15.68 0.003* 44.83 ± 0.40 49.16 ± 0.41 < 0.001*** LBMIG -0.65 ± 0.01 0 0.517 79.56 ± 6.52 78.91 ± 6.53 0.030* 45.16 ± 0.40 47.33 ± 1.21 0.003* ALL -0.79 ± 0.21 0 0.75 95.85 ± 20.59 95.06 ± 20.38 < 0.001*** 45.00 ± 0.74 46.25 ± 1.54 0.006* Note: HBMIG: High Body Mass Index Group, LBMIG: Low Body Mass Index Group, ALL = All Participants, BW= Body Weight, HCT= Hematocrit, kg=Kilograms, ml=Milliliters, %=Percentage value, p = Pre-Post Test Statistical Difference: *= p < 0.05,**= p < 0.00, ***= p < 0.001 Table 1 . The hydration level changes of the participant of within groups. **** Table 1 Nere Here **** 3.3.Prefrontal hemodynamic changes The prefrontal hemodynamic were assessed between group analyses before exercise. The results indicated that there was not a significant difference in Oxy-Hb (0.72 ± 0.25/-0.19 ± 0.56, p = 0.080), Deoxy-Hb (-0.02 ± 1.34/1.09 ± 0.69, p = 0.277), and Total-Hb (-0.11 ± 1.87/-0.90 ± 0.75, p = 0.277) levels between the HBMIG and LBMIG groups before exercise. After exercise, there were also no significant differences in Oxy-Hb (-0.01 ± 1.34/1.10 ± 0.72, p = 0.287), Deoxy-Hb (1.25 ± 1.48/0.52 ± 1.91, p = 401) and Total-Hb (1.24 ± 2.65/1.63 ± 2.53, p = 0.976) levels between the two groups. These results indicate that hemodynamic values changed over time before and after exercise. Table 2 presents changes in brain hemodynamic among all participants and groups. Table 2 Brain hemodynamic results pre and post exercise sessions analysis. Between Group Analysis Status Values p Status Values p Status Values P HBMIG Pre Oxy-Hb (mmol/L) 0.72 ± 0.25 0.080 HBMIG Pre Deoxy-Hb (mmol/L) -0.02 ± 1.34 0.277 HBMIG Pre Total-Hb (mmol/L) -0.11 ± 1.87 0.277 LBMIG Pre Oxy-Hb (mmol/L) -0.19 ± 0.56 LBMIG Pre Deoxy-Hb (mmol/L) 1.09 ± 0.69 LBMIG Pre Total-Hb (mmol/L) 0.90 ± 0.75 HBMIG Post Oxy-Hb (mmol/L) -0.01 ± 1.34 0.287 HBMIG Post Deoxy-Hb (mmol/L) 1.25 ± 1.48 0.401 HBMIG Post Total-Hb (mmol/L) 1.24 ± 2.65 0.976 LBMIG Post Oxy-Hb (mmol/L) 1.10 ± 0.72 LBMIG Post Deoxy-Hb (mmol/L) 0.52 ± 1.91 LBMIG Post Total-Hb (mmol/L) 1.63 ± 2.53 Within Group Analysis Status Pre Exercise Oxy-Hb (mmol/mL) Post Exercise Oxy-Hb (mmol/mL) p Pre Exercise Deoxy-Hb (mmol/mL) Post Exercise Deoxy-Hb (mmol/mL) p Pre Exercise Total-Hb (mmol/mL) Post Exercise Total-Hb (mmol/mL) p HBMIG 0.729 ± 0.25 -0.013 ± 1.34 0.338 -0.028 ± 1.34 1.259 ± 1.48 0.045* -0.214 ± 1.69 1.246 ± 2.5 0.050* LBMIG -0.190 ± 0.56 1.106 ± 0.72 0.028* 1.092 ± 0.52 0.901 ± 0.75 0.382 0.901 ± 0.75 1.634 ± 2.53 0.441 ALL 0.227 ± 0.6 0.307 ± 1.2 0.877 0.313 ± 1.25 -0.155 ± 1.91 0.446 0.541 ± 1.10 0.152 ± 2.55 0.559 Brain hemodynamic levels were assessed within-group analysis in the study groups, and post-exercise Oxy-Hb (0.227 ± 0.64/0.307 ± 1.27, p = 0.877), Deoxy-Hb (-0.313 ± 1.253/-0.155 ± 1.912, p = 0.446), and Total-Hb (0.541 ± 1.105/0.152 ± 2.558, p = 0.559) values (see Table 2 ). In the HBMIG group, an increase was observed in Deoxy-Hb (-0.028 ± 1.342/-1.259 ± 1.485, p = 0.045) and Total-Hb (-0.214 ± 1.697/1.246 ± 2.53, p = 0.050). Oxy-Hb (0.729 ± 0.252/-0.013 ± 1.349, p = 0.338) values did not show any significant changes. In the LBMIG group, an increase in Oxy-Hb (-0.190 ± 0.564/1.106 ± 0.724, p = 0.028) was observed; no significant changes were observed in Deoxy-Hb (1.092 ± 0.528/0.901 ± 0.752, p = 0.382) and total-Hb (0.901 ± 0.752/1.634 ± 2.536, p = 0.441) values. Table 2 . Brain hemodynamic results pre and post exercise sessions analysis. **** Table 2 Nere Here **** 3.4.Cognitive Response related to exercise Cognitive responses were evaluated between groups before exercise. The results indicated that the Correct Answers (18.33 ± 4.45/22.50 ± 6.92, p = 0.375), Correct Answers Reaction Time (RT) (492.50 ± 30.48/543.69 ± 98.72, p = 0.286), Wrong Answers (3.33 ± 1.40/6.66 ± 5.92, p = 0.354), Wrong Answers RT (641.33 ± 112.32/580.14 ± 64.92, p = 0.308) and Missed Answers (22.33 ± 4.96/17.50 ± 6.89, p = 0.314) counts did not show a significant difference. After exercise, a significant decrease was observed in the number of missed answers (22.33 ± 5.60/13.66 ± 3.67, p = 0.013) (see Fig. 2), while there was no significant difference in the number of correct answers (16.00 ± 6.06/23.50 ± 7.50, p = 0.106), correct answers reaction time (RT) (492.89 ± 95.72/539.57 ± 73.66, p = 0.236), wrong answers (6.16 ± 2.61/4.33 ± 3.07, p = 0.576), and wrong answers RT (574.13 ± 177.40/630.92 ± 200.42, p = 0.626). Table 3 shows the changes among all participants and groups. Table 3 Cognitive response of related to exercise. Between Group Analysis Status Values p Status Values p Status Values p HBMIG Pre Correct Answer 18.33 ± 4.45 0.375 HBMIG Pre Wrong Answer 3.33 ± 1.40 0.354 HBMIG Pre Miss Answer 22.33 ± 4.96 0.314 LBMIG Pre Correct Answer 22.50 ± 6.92 LBMIG Pre Wrong Answer 6.66 ± 5.92 LBMIG Pre Miss Answer 17.50 ± 6.89 HBMIG Post Correct Answer 16.00 ± 6.06 0.106 HBMIG Post Wrong Answer 6.16 ± 2.61 0.576 HBMIG Post Miss Answer 23.33 ± 5.60 0.013* LBMIG Post Correct Answer 23.50 ± 7.50 LBMIG Post Wrong Answer 4.33 ± 3.07 LBMIG Post Miss Answer 13.66 ± 3.67 Within Group Analysis Status Pre Correct Answer Post Correct Answer p Pre Wrong Answer Post Wrong Answer p Pre Miss Answer Post Wrong Answer p HBMIG 18.33 ± 4.45 16.00 ± 6.06 0.376 3.33 ± 2.33 6.16 ± 2.61 0.133 22.33 ± 4.96 23.33 ± 5.61 0.658 LBMIG 22.50 ± 6.92 23.50 ± 7.50 0.727 6.66 ± 5.92 4.33 ± 3.07 0.428 17.50 ± 6.89 13.66 ± 3.67 0.471 ALL 20.41 ± 5.94 19.75 ± 7.59 0.718 5.00 ± 4.93 5.35 ± 4.88 0.885 19.91 ± 6.25 19.08 ± 6.93 0.535 Note: HBMIG= High BMI Group, LBMIG = Low BMI Group, ALL = All Participants, p = Pre-Post Test Statistical Difference: *= p < 0.05, **= p < 0.00, ***= p < 0.001 Cognitive answers were assessed within group analysis in the study groups and post-exercise. The Correct Answer (20.41 ± 5.94/19.75 ± 7.59, p = 0.718), the Correct Answer RT (518.10 ± 74.61/516.23 ± 85.01, p = 0.926), the Wrong Answer (5.00 ± 4.93/5.35 ± 4.88, p = 0.885), the Wrong Answer RT (610.76 ± 93.12/602.52 ± 182.87, p = 0.857), and the Miss Answer (19.91 ± 6.25/19.08 ± 6.93, p = 0.535) values are not statistical differences. The HBMIG group, the Correct Answer (18.33 ± 4.45/16.00 ± 6.06, p = 0.376), the Correct Answer RT (492.50 ± 30.48/492.89 ± 95.72, p = 0.990), the Wrong Answer (3.33 ± 2.33/6.16 ± 2.61, p = 0.133), the Wrong Answer RT (641.33 ± 113.32/574.132 ± 177.40, p = 0.279), and the Miss Answer (22.33 ± 4.96/23.33 ± 5.61, p = 0.885) values are not statistical differences. In the LBMIG group, the Correct Answer (22.50 ± 6.92/23.50 ± 7.50, p = 0.727), the Correct Answer RT (543.69 ± 98.72/630.92 ± 200.42, p = 0.893), the Wrong Answer (6.66 ± 5.92/4.33 ± 3.07, p = 0.428), the Wrong Answer RT (580.14 ± 64.92/630.92 ± 200.42, p = 0.471), and the Miss Answer (17.50 ± 6.89/13.66 ± 3.67, p = 0.471) values are not statistical differences (see Table 3 ). Table 3 . Cognitive response of related to exercise. **** Table 3 Nere Here **** **** Fig. 2 Nere Here **** Note The light-colored column represents HBMIG data, while the dark-colored column represents LBMIG data. Figure 2. All group Post Exercise Cognitive Response. 4. Discussion This study investigates the effect of body mass index on prefrontal cortex hemodynamic and cognitive functions in exercise-induced hypohydration in male athletes. The main finding of the study was that oxyhemoglobin values increased significantly in cognitive tasks during exercise-related hypohydration conditions in the LBMIG, while deoxyhemoglobin values increased significantly in the HBMIG. Therefore, missing answers increased significantly in the HBMIG cognitive test results. The changes in body weight and hematocrit following the hypohydration condition created in our study are like those observed in participant groups with similar BMI levels in studies conducted under laboratory and real field conditions in the literature [ 57 – 59 ]. Specifically, hypohydration effects are noticeable in studies with long-interval exercise. Juett et al. induced a body weight loss of 1% using the Loughborough shuttle run (15x6 min/2 min rest between sit-ups) in 14 active male athletes with a BMI of 23.6 ± 2.6 kg/m² [ 58 ]. James et al. evaluated the performance of nine healthy participants in intermittent exercise (8x10 min cycle/5 min rest) followed by 15 min time trial cycling. At the end of the study, the participants had lost ~ 1.5% of their body weight [ 57 ]. Brun et al. observed the effects of 30 minutes of submaximal exercise on hematocrit values. They observed an increase in hematocrit values taken immediately after exercise. This change is in line with the results of our study [ 35 ]. As a result of the study, the oxyhemoglobin values of the participants in the LBMIG increased significantly during the cognitive task under the EIH. It has been reported in the literature that physically fit athletes exhibit chronic adaptations in exercise-induced forebrain hemodynamic responses and work more efficiently [ 60 ]. Kim et al. performed a 2-back task on 16 healthy men before and after 10 minutes of moderate and high-intensity aerobic exercise. Participants' performance on the 2-back task allowed assessment of hemodynamic changes in the prefrontal cortex. At the end of the study, they reported that during the 2-back test, an oxyhemoglobin increase in the dorsolateral prefrontal cortex was observed under moderate and high-intensity exercise conditions [ 2 ]. Oxyhemoglobin level is considered an indicator of increased neuronal workload. This increase in pre- and post-exercise oxyhemoglobin levels may be an indicator of increased neuronal efficiency in the LBMIG due to the beneficial effects of exercise. In particular, the fact that local microcirculation is not impaired despite the increased workload on the forebrain during the cognitive task may indicate that the LBMIG endures hypohydration conditions. This interpretation supports the finding that cognitive test results were not adversely affected in the LBMIG. Our study found that deoxyhemoglobin levels increased significantly during cognitive tasks in HBMIG participants under EIH conditions. This response may indicate a poorer neurovascular match to similar cognitive loads under EIH conditions. This finding is supported by significantly increased miss scores in cognitive tasks. Our unique study design has resulted in the absence of any comparable studies conducted under similar conditions. This finding has been discussed in the context of BMI levels, stress, cognition, and brain responses. In the literature, Jones et al. evaluated the activity of the dorsolateral prefrontal cortex in overweight adults (body mass index: 28.56 ± 4.95 kg/m²) after 15 minutes of cycling exercise. They reported higher dorsolateral prefrontal cortex activity immediately post-exercise [ 60 ]. Soares et al. non-invasively assessed differences in oxidative metabolism in overweight compared to normal-weight individuals in normal-weight and overweight subjects using near-infrared spectroscopy and the occlusion stress. It has been reported that an increase in deoxyhemoglobin levels occurs when blood flow is restricted in people who are overweight [ 61 ]. From a cognitive perspective, a study conducted on a large group of young participants found a negative correlation between BMI and general cognitive abilities [ 62 ]. Considering the results of our HBMIG participants and the literature presented, it is believed that high BMI values cause the hemodynamic responses of the forebrain and executive function to be more vulnerable and prone to impairment under physical and cognitive stress. Based on cognitive test results in the EIH condition after prolonged exercise, no significant change was found in the number of correct answers (Δ = +1), wrong answers (Δ = +2.33), or missing answers (Δ = -3.84) in the LBMIG, indicating that cognitive performance was maintained, and no deterioration occurred. On the other hand, while a numerical increase in missing answers (Δ = +1) was observed in HBMIG, a numerical decrease in the number of correct answers (Δ = -2.33) and a numerical increase in the number of wrong answers (Δ = +2.83) were observed. In the between-group comparison, HBMIG missing answers increased significantly in the EIH condition compared to LBMIG (p = 0.013). There are hardly any studies in the literature investigating the effects of prolonged exercise on cognition. Executive functions and exercise duration have a significant functional link, particularly in prolonged exercise [ 63 – 65 ]. Tempest et al. evaluated the effect of 60 minutes of low-load, prolonged exercise on cognitive function using the 2-back task with 14 participants. They found only an increase in the number of correct answers, with no change in other responses [ 66 ]. This finding is consistent with the results of the only LBMIG in our study. In addition, studies in the literature on exercise intensity and cognition have shown significant changes in the number of correct and wrong responses as well as the number of missed serial responses at moderate and high-intensity exercises in fit athletes [ 65 , 66 ]. In more detail, Cantelon et al.'s comprehensive review study found that incremental exercise from very low to moderate levels could lead to minor enhancements in working memory [ 63 ]. In our study, we observed that 30 minutes of aerobic exercise followed by 15 minutes of high-intensity interval exercise had a protective effect on executive functions in the LBMIG and a negative effect on the HBMIG in the 2-back condition. This information may indicate that BMI is a parameter that affects cognitive function during prolonged exercise. In our research, the high-intensity interval model following constant load exercise had a detrimental impact on cognitive function in individuals with a high BMI. As a possible physiological mechanism for this result obtained in our study, exercise maintenance with fluid deprivation in the HBMIG may have increased resource utilization during the mental task, consequently increasing the resource consumption observed during cognitive tasks and the inability of HBMI groups to maintain task continuity by taking involuntary breaks (missing value). Future studies are needed to investigate the effects of exercise on cognition based on neurophysiological factors in different populations (gender, age, BMI) and conditions (dehydration, cold, heat, humidity, etc.). Limitation Due to the thermodynamic effects immediately following exercise, fluid loss continued, contributing to dehydration as measured. Unfortunately, the assessment did not include this aspect of fluid loss. Future studies should aim for more profound investigations with larger participant groups. Nevertheless, we believe our findings will be valuable in drawing attention to the issue. In addition, our group consisted of athletes actively competing in national and international leagues and due to the circumstances related to COVID-19, it was difficult to reach a larger number of athletes, leading to low sample sizes for both groups. Therefore, a larger sample size (if possible) should be used in further studies to confirm, refute, and/or extend our findings. 5. Conclusions Exercise-induced hypohydration had a detrimental impact on prefrontal cortexoxygenation and cognitive functions, particularly in athletes with a high BMI. On the other hand, athletes with low BMI values who participated in our study demonstrated higher neural efficiency and stable cognitive performance under physical stress. These results may highlight that athletes with high BMI values who participate in sports requiring high physical exertion and executive function-based cognitive skills should be more careful about exercise-induced dehydration conditions. Practical Applications Individual plans tailored to athletes with high BMI values are necessary to prevent exercise-induced dehydration. Sports field staff and experts should monitor the amount of fluid and electrolytes lost by athletes during matches or training sessions. Environmental factors like heat, cold, and humidity should be carefully considered in this monitoring. Sports with high cognitive demands should prioritize addressing this issue. We recommend ‘awareness education’ on the cognitive and physiological adverse effects of dehydration in athletes with high BMI values. Abbreviations The following abbreviations are used in this manuscript: BMI Body Mass Index LBMIG Low BMI Group HBMIG Heigh BMI Group EIH Exercise-Induced Hypohydration PFC Prefrontal Cortex (PFC), SMA Supplementary Motor Area fNIRS Functional Near-Infrared Spectroscopy Oxy-Hb Oxygenated Brain Tissue Deoxy-Hb Deoxygenated Hemoglobin BW Body Weight Hct Hematocrit SIT Sprint Interval Training Declarations Author Contributions: Conceptualization, E.G and E.U; methodology, C.B., E.U., E.M., C.G., E.G.; formal analysis, E.U.,C.G. and E.G.; investigation, C.B. E.U.,E.G.,C.G. and E.M.; writing—original draft preparation, E.U., E.G., C.G., E.M., C.B. ; writing—review and editing, E.U., E.G., C.G., E.M., supervision, E.G. All authors have read and agreed to the published version of the manuscript. Funding: This research received no external funding Institutional Review Board Statement: This study was reviewed by the Dokuz Eylül University Non-Invasive Research Ethics Committee and approved by decision no. 2020/07-28 dated 13 April 2020 and was conducted in accordance with the Helsinki Declaration. Informed Consent Statement: Written informed consent to participate in this study was provided by the participant’s legal guardian/next of kin. Informed consent was obtained from all individual participants included in the study. Data Availability Statement: All collected data in the current study are available after obtaining permission from all the authors. Written proposals can be addressed to the corresponding authors for appropriateness of use. The data are not publicly available due to privacy and ethical reasons. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-8820751","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":594974257,"identity":"88e27768-1f9b-4f31-9e5e-8f7105df731f","order_by":0,"name":"Cigdem Bediz","email":"","orcid":"","institution":"University of Kyrenia","correspondingAuthor":false,"prefix":"","firstName":"Cigdem","middleName":"","lastName":"Bediz","suffix":""},{"id":594974258,"identity":"73fab519-d5ba-4121-ba89-1668201b762a","order_by":1,"name":"Erdem Uylas","email":"","orcid":"","institution":"Dokuz Eylül University","correspondingAuthor":false,"prefix":"","firstName":"Erdem","middleName":"","lastName":"Uylas","suffix":""},{"id":594974259,"identity":"2eb0b182-d9c7-47b0-96a8-d605658b2fa2","order_by":2,"name":"Cagdas Guducu","email":"","orcid":"","institution":"Dokuz Eylül University","correspondingAuthor":false,"prefix":"","firstName":"Cagdas","middleName":"","lastName":"Guducu","suffix":""},{"id":594974260,"identity":"b68da82d-d346-4839-bedf-f04948f7cea7","order_by":3,"name":"Egemen Manci","email":"","orcid":"","institution":"Izmir Democracy University","correspondingAuthor":false,"prefix":"","firstName":"Egemen","middleName":"","lastName":"Manci","suffix":""},{"id":594974261,"identity":"4a330eb9-4143-4ae3-8572-029941945285","order_by":4,"name":"Erkan Gunay","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA9ElEQVRIiWNgGAWjYFACNjiL8QFjA4hOIF4LswFcywEitbBJEKWFX/pY4ucChtrE7exnzCp+7jjMwM+eY8D8cQ9uLZJ9aYelZzAcT9zZk2N2s/fMYQbJnjcGDAee4dZicIa9QZqH4VjihgM5ZrcZ2w4zGNzIAWrB4zL7M+zNv8Fazr8xKwZpsSekxYCH7RjQlprEDTdyzJjBtkgQ0CJxhi3NmsfggPGGG8+KJXvPpPNInHlWcOAMHi38PWzGt3kq6mQ3nE/e+OHnDms5/vbkjQ8q8GiBOu8wkOAwADF5QARBDUBQB8TsD4hQOApGwSgYBSMRAAAkClTcNNzoGQAAAABJRU5ErkJggg==","orcid":"","institution":"Manisa Celal Bayar University","correspondingAuthor":true,"prefix":"","firstName":"Erkan","middleName":"","lastName":"Gunay","suffix":""}],"badges":[],"createdAt":"2026-02-08 10:08:42","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-8820751/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-8820751/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":103349139,"identity":"614bba08-2e13-4da3-b625-1700a343beb4","added_by":"auto","created_at":"2026-02-24 16:41:02","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":307931,"visible":true,"origin":"","legend":"\u003cp\u003eStudy Design\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-8820751/v1/aea8fbdc1fe83a40e6b0b994.png"},{"id":103349036,"identity":"dc3a0d22-429e-4e2b-a0bd-68fd5453b0e9","added_by":"auto","created_at":"2026-02-24 16:40:46","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":22409,"visible":true,"origin":"","legend":"\u003cp\u003eAll group Post Exercise Cognitive Response.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-8820751/v1/45fb044454d3fb8b5e8f1b1e.png"},{"id":103349224,"identity":"b57882f3-d3b6-4626-aff2-45254a66eeac","added_by":"auto","created_at":"2026-02-24 16:41:27","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1724053,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8820751/v1/ac41bf4d-6fde-4d11-9b7f-177669a929cd.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"The Effect of Body Mass Index on Prefrontal Cortex Hemodynamic and Cognitive Functions In Exercise-Induced Hypohydration in Male Athletes","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eBody mass index (BMI) is a critical parameter that is used to measure overall health. In the general population, a BMI value range of 18.5 to 24.9 kg/m\u0026sup2; is considered normal, while a value range of 25 to 29.9 kg/m\u0026sup2; is considered high BMI. A high BMI is regarded as a major contributing factor to a wide range of health concerns, primarily metabolic disorders and cardiovascular diseases. Recent studies have indicated that BMI levels may have a negative impact on brain hemodynamics [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e] and cognitive performance [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. On the other hand, for elite athletes and bodybuilders, high BMI values are associated with increased muscle mass and the resulting increase in BMI, so it is not correct to directly correlate them with overall health [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAthletic populations consist of individuals with a high lean body mass ratio relative to their height and typically have high BMI values [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. However, body composition significantly influences performance in many sports. Especially in endurance-based performances, a high BMI can act as a limitation factor [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. This limitation suggests a negative correlation between BMI and VO₂ max, implying that BMI may influence cardiovascular endurance [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Additionally, fluid and sodium imbalances during exercise in athletes with high BMI support this notion. This is because it is known that athletes with high BMI experience greater exercise-related fluid losses compared to those with low BMI [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eProlonged exercise can result in a state of dehydration. For instance, a field study of elite endurance athletes competing in international marathons revealed that body weight can decrease by 1.7% to 6.6% post-race [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. These values are a significant indicator of the heightened physical stress experienced by athletes. The predominant factor contributing to this stress is exercise-induced hypohydration (EIH). EIH has been shown to negatively affect blood flow in microvascular circulation because there is less water in the blood and a higher concentration of hematocrit [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. This effect has been demonstrated to have a detrimental effect on perfusion in peripheral tissues, resulting in hemodynamic deteriorations such as insufficient oxygenation and nutrition of active cells [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. Impaired hemodynamics have the effect of reducing the amount of blood returning to the heart, which in turn increases the load on the heart [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. The adverse effects of EIH on the cardiovascular system have been demonstrated in studies, with symptoms including increased heart rate, decreased stroke volume, and elevated blood pressure [\u003cspan additionalcitationids=\"CR14\" citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eRecent research has focused on the relationship between hypohydration, brain responses, and cognitive performance [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e, \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Hypohydration reduces the volume of the cerebellum and thalamus, disrupts the brain's osmotic balance, but does not affect total cerebral blood volume [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. On the other hand, a study has shown that hypohydration causes greater BOLD signal increases in brain regions associated with visual-motor tasks and learning, such as the prefrontal cortex (PFC), supplementary motor area (SMA), hippocampus, and striatum [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Another related study reported that hypohydration causes a temporary increase in PFC activation and that this change in blood flow affects cognitive performance Some cognitive-based studies have shown that hypohydration negatively affects cognitive processes such as information processing, decision making, problem solving, attention, memory, and motor coordination [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDuring a cognitive task, cortical tissue is activated, and changes in chromophores occur. This reveals changes in the neural system, and the responses during the task can be measured by neuroimaging devices [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Functional near-infrared spectroscopy (fNIRS) is a technique frequently employed to image brain hemodynamic responses [\u003cspan additionalcitationids=\"CR25\" citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. This examination uses near-infrared light at different wavelengths to distinguish between oxygenated brain tissue (Oxy-Hb) and deoxygenated hemoglobin (Deoxy-Hb) tissue concentrations [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. These changes enable the observation of oxygen consumption associated with neurovascular coupling during various tasks and conditions. Oxygen consumption in the brain provides information about the metabolic demand of a task [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eBased on the information presented above, this study aims to investigate the differences in hemodynamic and cognitive performance of athletes with different BMI levels under EIH conditions. The hypotheses of the study are: i) Athletes with high BMI use more oxygen during cognitive tasks under EIH conditions, resulting in increased deoxyhemoglobin levels. ii) Athletes with low BMI exhibit more economical prefrontal oxygenation responses during cognitive tasks under EIH conditions. iii) Athletes with high BMI may exhibit cognitive impairments under EIH conditions compared to athletes with low BMI. We believe that this unique approach has the potential to contribute to elucidating the effects of BMI on the relationship between neurocognition and sports performance.\u003c/p\u003e"},{"header":"2. Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1. Participants\u003c/h2\u003e \u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eTwelve healthy male competitive athletes between 18 and 29 years of age were recruited. All participants were selected from individuals who had previously participated in bicycle ergometer-based exercise tests conducted in our laboratory and were well adapted. The participants characteristics were as follows (mean\u0026thinsp;\u0026plusmn;\u0026thinsp;SD): age 20.85\u0026thinsp;\u0026plusmn;\u0026thinsp;4.0 years, training age 7.8\u0026thinsp;\u0026plusmn;\u0026thinsp;4.2 years, body mass 97.0\u0026thinsp;\u0026plusmn;\u0026thinsp;19.6 kg, height 184.66\u0026thinsp;\u0026plusmn;\u0026thinsp;5.01 cm. The number of participants was calculated using the G-Power 3.1.9.4 software (Heinrich Heine University D\u0026uuml;sseldorf, Germany) to predetermine the required sample size (T-test: Difference Between Two Dependent Means-Matched Pairs). To estimate the sample size required to determine the effects of a physical exercise session on Hemodynamic and cognitive performance in athletes, we used an effect size of f\u0026thinsp;=\u0026thinsp;1.70 with an alpha (error) rate of 5% and a power of 90%. The determination in G-Power resulted in a sample size of 5 participants. Due to the overlap of the data collection process with the COVID-19 pandemic, the planned number of participants was kept at a low level. The study was planned to start with 12 participants to prevent data loss that may arise from risks during measurements and analysis results. [\u003cspan additionalcitationids=\"CR30 CR31\" citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. The inclusion criteria for the study were regular training, a sports history of at least five years, and no recent lower extremity injury. Exclusion criteria were low lower limb power, injury, and irregular training. Participants were informed of the details of the test procedures, the risks involved, the measures taken, and any special instructions or risks. All participants completed the informed consent form, and their voluntary participation in the study was documented. The xxx University Non-Invasive Research Ethics Committee approved this study with the decision number 2020/07\u0026ndash;28 dated April 13, 2020.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2.Study Design\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe research comprised two distinct sessions: a familiarisation session and an experimental intervention session. The familiarisation session spanned around 20 minutes, whereas the experimental intervention session lasted approximately 75 minutes. Throughout both the familiarisation and experimental intervention visits, participants were instructed not to engage in strenuous physical activities. All experimental sessions were executed under normothermic conditions, maintaining a temperature of 25.7\u0026thinsp;\u0026plusmn;\u0026thinsp;0.5\u0026deg;C and a relative humidity of 41.3%, as indicated by the thermometer readings. Thus, there was assurance that the participants had the same hydration levels at the start of both conditions [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. Figure\u0026nbsp;1 illustrates the applied research design for the combined familiarisation and practice sessions. The data collection process was conducted between 1 May 2020 and 1 December 2020.\u003c/p\u003e \u003cp\u003e \u003cb\u003e**** Fig.\u0026nbsp;1 Nere Here ****\u003c/b\u003e \u003c/p\u003e \u003cp\u003e \u003cb\u003eFigure 1.\u003c/b\u003e Study Design.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cdiv id=\"Sec5\" class=\"Section3\"\u003e \u003ch2\u003e2.2.1.Pre-Session Standardization\u003c/h2\u003e \u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe participants commenced both sessions concurrently from 12 to 4 p.m. fluid consumption was ceased one hour before each session, while food intake was stopped two hours before both sessions. Furthermore, upon the participants' arrival at the laboratory before each session, inquiries were made regarding their thirst levels, their body weight was recorded, and it was confirmed that they were close to their weight during the initial session. This protocol ensured that participants initiated the exercise regimen adequately hydrated. Additionally, participants were instructed to refrain from alcohol consumption and vigorous exercise within the 24 hours preceding the two assessments.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section3\"\u003e \u003ch2\u003e2.2.2.Familiarisation Session\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eAll participants completed the informed consent form, and their voluntary participation in the study was documented. In the first phase, participants were informed about the experimental protocol, and demographic information was collected. Afterward, anthropometric measurements were taken. Baseline body weight (BW) and hematocrit (HCT) values were measured. Five minutes of fNIRS during the 2-back test were recorded. During this process, the teaching of the 2-step test and adaptation to the test were carried out.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section3\"\u003e \u003ch2\u003e2.2.3.Anthropometric Measurements\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe height was measured using a manual stadiometer. When participants stood upright with their backs to the stadiometer and bare feet, their height was measured by determining the top of their heads and recorded in centimeters. The body mass index (BMI) calculation was calculated using the formula below [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003cb\u003eBMI\u0026thinsp;=\u0026thinsp;Body Weight (kg.) / Height (m) \u0026sup2; = kg/m\u0026sup2;\u003c/b\u003e \u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec8\" class=\"Section3\"\u003e \u003ch2\u003e2.2.4.Hydration Status Measurement\u003c/h2\u003e \u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eIn the study, changes in body weight and hematocrit were used to establish a constant baseline hydration status [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e, \u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. At the start of the exercise session, participants were found to have similar weight and hematocrit values to those measured at the start of the acclimatization session. In addition, feedback was obtained from the participants before the sessions that they were fully hydrated and that they were drinking fluids. Levels of hypohydration were determined by measuring both pre- and post-exercise sessions. In this assessment, BW and HCT measurements were taken together. A decrease in body weight and an increase in HCT indicate the assets of hypohydration [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e, \u003cspan citationid=\"CR36\" class=\"CitationRef\"\u003e36\u003c/span\u003e]. Body weight was measured using an electronic scale. The participants stood barefoot and upright on the electronic scale until it displayed the results. The data obtained was recorded in kilograms. Hematocrit was measured before the session and at the end of the exercise. During the measurements, the participant's fingertip was pricked with a lancet, and approximately 70\u0026ndash;80 microliters of blood (3\u0026ndash;4 drops) were taken into two heparin tubes and filled to 2/3 of the tube. The heparinised tubes were placed in a centrifuge (N\u0026uuml;ve NT 715), and they were centrifuged for 4 minutes at 9000\u0026ndash;10000 rpm [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e].\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section3\"\u003e \u003ch2\u003e2.2.5.Prefrontal Hemodynamic Measurement\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eParticipants' prefrontal hemodynamics were recorded while seated and during five minutes of cognitive testing. The Functional Near-Infrared Spectroscopy (fNIRS) system (Biopac, fNIRS DEVICES, Imager 1100, LLC, MD, USA) was used to measure changes in the blood flow in the prefrontal cortex. During the measurements, a flexible sensor pad consisting of 4 light sources with peak wavelengths of 730 nm and 850 nm and 12 detectors (4 light sources), which are 16 parts of this system, was connected to the participants' foreheads (RXFNIRA sensors real-time recording). Data was collected from 16 channels. Hemodynamic changes in cortical areas were then monitored [\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. Before recording, the forehead area was cleaned with an alcohol swab. After cleaning, the sensor pad was placed on the forehead, and the optodes were wrapped tightly around the forehead with a specially designed elastic black bandage to limit sensor pad artefacts caused by head movement [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. The purpose of this choice was to eliminate possible ambient light and not create artefacts [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section3\"\u003e \u003ch2\u003e2.2.6.fNIRS Data Analysis\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe fNIRS data were collected in blocks for the duration of the 2-back test battery. The 2-back battery of tests was carried out during the pre- and post-testing sessions. This battery lasted for approximately 4 minutes, and blocks were recorded for 120 stimulus presentations. During test processing block recording, the fNIRS system continuously collected signals from oxygenated hemoglobin (Oxy-Hb) and deoxygenated hemoglobin (Deoxy-Hb). Correct, wrong and missed answers, as well as correct and wrong reaction times, are collected in a separate cognitive data file [\u003cspan additionalcitationids=\"CR43\" citationid=\"CR42\" class=\"CitationRef\"\u003e42\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e44\u003c/span\u003e]. Data collection and visualisation were performed using COBI Studio software [\u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e43\u003c/span\u003e]. The data obtained using COBI Studio were analysed using the fNIRSoft Pro version data collected from the 16 channels analysed. Then, the FIR filtering method (System 1200S-2 Hz) was applied to remove the general and motion-related distortions from the data. Then, considering the methods suggested by Ayaz et al., the SMAR (Applying Motion Artefact Rejection) method was applied, and the obtained data were used for statistical analysis [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e, \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e, \u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section3\"\u003e \u003ch2\u003e2.2.7.Exercise Session\u003c/h2\u003e \u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe exercise protocol applied attempted to simulate the loads that athletes are exposed to in real field conditions. In the study, BW and HCT measurements were taken before the exercise session, and five minutes of fNIRS were recorded during the 2-back task. Then, participants warmed up and stretched individually for five minutes. After the warm-up, participants engaged in 30 minutes of constant submaximal exercise. The Submaximal Constant-Load Cycle exercise was applied to participants in the submaximal exercise session. Before exercise, the participants' sitting height on the pre-session cycle ergometer corresponded to the iliac bone of the ergometer seat (Monark, LC6, Verberg, Sweden) [\u003cspan citationid=\"CR45\" class=\"CitationRef\"\u003e45\u003c/span\u003e, \u003cspan citationid=\"CR46\" class=\"CitationRef\"\u003e46\u003c/span\u003e]. After this procedure, they were asked to pedal for two minutes unloaded to adapt to the ergometer, and adaptation was achieved before the protocols. During the submaximal cycling exercise protocol, the participants performed the exercise session in both conditions by pedaling at 60 rpm/100 watts for 30 minutes. After 5 minutes of passive rest, the Sprint Interval Training (SIT) protocol was started. This protocol was chosen to elicit anaerobic performance (20 seconds - all-out). Participants performed four tests (SIT-1, SIT-2, SIT-3, SIT-4) using a bicycle ergometer (Monark LC7; Monark, Vansbro, Sweden) with active recovery (Recovery-1, Recovery-2, and Recovery-3) with a load of 100 watt/60 rpm for 2 minutes between these tests [\u003cspan additionalcitationids=\"CR48\" citationid=\"CR47\" class=\"CitationRef\"\u003e47\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR49\" class=\"CitationRef\"\u003e49\u003c/span\u003e]. After the exercise session, all measures were repeated.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section3\"\u003e \u003ch2\u003e2.2.8.N-Back (2-Back) Cognition Task\u003c/h2\u003e \u003cp\u003e\u003cdiv class=\"BlockQuote\"\u003e\u003cp\u003eThe 2-back cognition task is a widely used test of working memory function. This test measures the recognition and reaction time of letters placed two behind the letter index that appears on the computer screen in a mixed order [\u003cspan citationid=\"CR50\" class=\"CitationRef\"\u003e50\u003c/span\u003e]. For the cognitive test, participants were seated 70\u0026ndash;90 cm from the computer screen, as suggested by Chu et al. [\u003cspan citationid=\"CR51\" class=\"CitationRef\"\u003e51\u003c/span\u003e]. The computer used for tests was a 13-inch Apple Macbook Air 2017 with a 1440x900 screen resolution in a 16:10 aspect ratio and a 1.8 GHz dual-core Intel Core i5 processor [\u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e52\u003c/span\u003e]. A 2-back test was performed on Pebl Launcher for Pebl version 2.1[\u003cspan citationid=\"CR53\" class=\"CitationRef\"\u003e53\u003c/span\u003e]. The test battery contains 40 target stimuli and 80 non-target stimuli. Correct, wrong and missed answers, as well as correct and wrong reaction times, are collected in a separate cognitive data file. Responses to these stimuli, including correct, wrong, and missed responses, as well as correct and wrong response times, are collected in a separate cognitive data file. Subsequently, the data obtained were analysed to evaluate the participants' executive functions under cognitive loads. The details of the test application are presented below [\u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e54\u003c/span\u003e]. At the beginning of each session (pre- and post-test), adaptation (familiarisation) was achieved by administering a 1-back and then a 2-back to allow participants to recognize and try out the test. To eliminate the learning effect, the test was explained to participants during a familiarisation session and then administered. The researchers administered the main part of the test. In the main part, the stimuli were presented to the participants by a series of white capital letters (\"C\", \"H\", \"K\", \"N\", \"R\", \"W\", \"X\", \"Y\") on a black background in the middle of the computer screen. Inter-stimulus interval: 1500 milliseconds (ms.), and the number of stimuli was fixed at 120. Participants pressed the left shift key on the keyboard if a letter on the screen matched the two letters behind it. The test took about 4 minutes to complete. To assess working memory performance [\u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e55\u003c/span\u003e], the number of correct and wrong responses to stimuli and the reaction times of these responses were recorded and analysed [\u003cspan citationid=\"CR54\" class=\"CitationRef\"\u003e54\u003c/span\u003e, \u003cspan citationid=\"CR55\" class=\"CitationRef\"\u003e55\u003c/span\u003e]. As a result of this test, the number of correct answers, the reaction time for correct answers, the number of wrong answers, the reaction time for wrong answers, and the number of missed answers were totalled and evaluated.\u003c/p\u003e\u003c/div\u003e\u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e2.3.Statistical Analysis\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eAll statistical analyses were performed with a statistical package (JASP\u0026mdash;just another statistical program, version 0.16.3). All participants were divided into two groups based on a BMI cut-off of 27. Those with a score above 27 were called HBMIG, while those below 27 were LBMIG [\u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e]. Afterward, the Shapiro-Wilk test was applied to determine the normal distribution of data (body weight, hematocrit, oxyhemoglobin, deoxyhemoglobin, total hemoglobin, correct, wrong, missing, and reaction times). It was determined that the data were normally distributed. Before and after the exercise session was performed using a paired sample t-test. In addition, for different BMI, the paired sample t-test was used to compare the data (body weight, hematocrit, oxyhemoglobin, deoxyhemoglobin, total hemoglobin, correct, wrong, missing, and reaction times) in the high body mass index and low body mass index groups. In addition to the comparisons, the effect sizes of the data between each other were determined using the Cohen d. The statistical significance level was determined as less than 0.05 in statistical analyses (p\u0026thinsp;\u0026lt;\u0026thinsp;0.05) [\u003cspan citationid=\"CR56\" class=\"CitationRef\"\u003e56\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e \u003ch2\u003e3.1.Participants\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe study participants were divided into two groups: the high body mass index group (HBMIG) and the low body mass index group (LBMIG). The HBMIG had an average age of 21.33\u0026thinsp;\u0026plusmn;\u0026thinsp;4.59 years, an average training age of 8.66\u0026thinsp;\u0026plusmn;\u0026thinsp;4.88 years, an average height of 186.83\u0026thinsp;\u0026plusmn;\u0026thinsp;5.03 cm, a body weight of 112.01\u0026thinsp;\u0026plusmn;\u0026thinsp;16.25 kg, and a BMI of 32.45\u0026thinsp;\u0026plusmn;\u0026thinsp;6.05 kg/m\u0026sup2;; in contrast, the LBMIG consisted of 6 participants with an average age of 19.50\u0026thinsp;\u0026plusmn;\u0026thinsp;2.07 years, a training age of 7.00\u0026thinsp;\u0026plusmn;\u0026thinsp;3.22 years, a height of 182.50\u0026thinsp;\u0026plusmn;\u0026thinsp;4.32 cm, a body weight of 82.06\u0026thinsp;\u0026plusmn;\u0026thinsp;6.52 kg, and a BMI of 24.64\u0026thinsp;\u0026plusmn;\u0026thinsp;2.02 kg/m\u0026sup2;. The average values for all groups of participants were as follows: age 20.42\u0026thinsp;\u0026plusmn;\u0026thinsp;5.13 years; training age 8\u0026thinsp;\u0026plusmn;\u0026thinsp;4 years; height 183.90\u0026thinsp;\u0026plusmn;\u0026thinsp;4.48 cm; body weight 97.20\u0026thinsp;\u0026plusmn;\u0026thinsp;4.48 kg; and BMI 25\u0026thinsp;\u0026plusmn;\u0026thinsp;11.86 kg/m\u0026sup2;.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec16\" class=\"Section2\"\u003e \u003ch2\u003e3.2.Hydration status-related exercise\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe body weight values of the HBMIG and LBMIG groups were compared before (p\u0026thinsp;=\u0026thinsp;0.01) and after exercise, and a significant decrease was found (p\u0026thinsp;=\u0026thinsp;0.01). Hematocrit values did not change significantly before and after exercise (p\u0026thinsp;=\u0026thinsp;0.360 and p\u0026thinsp;=\u0026thinsp;0.113, respectively) (see Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e). Pre- and post-exercises in within-group values were examined. In terms of body weight, a significant decrease of 0.92% (p\u0026thinsp;=\u0026thinsp;0.003) was observed in the HBMIG group, 0.65% (p\u0026thinsp;=\u0026thinsp;0.30) in the LBMIG group, and 0.79% (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) in all participants. In HCT values, significant increases were found in the HBMIG group (p\u0026thinsp;=\u0026thinsp;0.004), LBMIG group (p\u0026thinsp;=\u0026thinsp;0.002), and all groups (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001) (see Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\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\u003eThe hydration level changes of the participant of within groups.\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=\"char\" char=\"\u0026plusmn;\" 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=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" 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=\"\u0026plusmn;\" class=\"colspec\" colname=\"c8\" colnum=\"8\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\"\u0026plusmn;\" class=\"colspec\" colname=\"c9\" colnum=\"9\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c10\" colnum=\"10\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStatus\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eTotal\u003c/p\u003e \u003cp\u003eBody\u003c/p\u003e \u003cp\u003eMass Loss\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eLiquid\u003c/p\u003e \u003cp\u003eIntake\u003c/p\u003e \u003cp\u003e(ml)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eHydration\u003c/p\u003e \u003cp\u003eStatus\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003cp\u003eExercise\u003c/p\u003e \u003cp\u003eBW\u003c/p\u003e \u003cp\u003e(kg)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003cp\u003eExercise\u003c/p\u003e \u003cp\u003eBW\u003c/p\u003e \u003cp\u003e(kg)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c8\"\u003e \u003cp\u003ePre\u003c/p\u003e \u003cp\u003eExercise\u003c/p\u003e \u003cp\u003eHCT\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c9\"\u003e \u003cp\u003ePost\u003c/p\u003e \u003cp\u003eExercise\u003c/p\u003e \u003cp\u003eHCT\u003c/p\u003e \u003cp\u003e(%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c10\"\u003e \u003cp\u003e\u003cem\u003ep\u003c/em\u003e\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHBMIG\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e-0.92\u0026thinsp;\u0026plusmn;\u0026thinsp;0.22\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e1,031\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e112.13\u0026thinsp;\u0026plusmn;\u0026thinsp;15.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e \u003cp\u003e111.21\u0026thinsp;\u0026plusmn;\u0026thinsp;15.68\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.003*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c8\"\u003e \u003cp\u003e44.83\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c9\"\u003e \u003cp\u003e49.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.41\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLBMIG\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e-0.65\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.517\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e79.56\u0026thinsp;\u0026plusmn;\u0026thinsp;6.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e \u003cp\u003e78.91\u0026thinsp;\u0026plusmn;\u0026thinsp;6.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.030*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c8\"\u003e \u003cp\u003e45.16\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c9\"\u003e \u003cp\u003e47.33\u0026thinsp;\u0026plusmn;\u0026thinsp;1.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e\u003cb\u003e0.003*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eALL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c2\"\u003e \u003cp\u003e-0.79\u0026thinsp;\u0026plusmn;\u0026thinsp;0.21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c5\"\u003e \u003cp\u003e95.85\u0026thinsp;\u0026plusmn;\u0026thinsp;20.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c6\"\u003e \u003cp\u003e95.06\u0026thinsp;\u0026plusmn;\u0026thinsp;20.38\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e\u0026lt;\u0026thinsp;0.001***\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c8\"\u003e \u003cp\u003e45.00\u0026thinsp;\u0026plusmn;\u0026thinsp;0.74\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\"\u0026plusmn;\" colname=\"c9\"\u003e \u003cp\u003e46.25\u0026thinsp;\u0026plusmn;\u0026thinsp;1.54\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c10\"\u003e \u003cp\u003e\u003cb\u003e0.006*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"10\"\u003eNote: HBMIG: High Body Mass Index Group, LBMIG: Low Body Mass Index Group, ALL\u0026thinsp;=\u0026thinsp;All Participants, BW= Body Weight, HCT= Hematocrit, kg=Kilograms, ml=Milliliters, %=Percentage value, p\u0026thinsp;=\u0026thinsp;Pre-Post Test Statistical Difference: *= p\u0026thinsp;\u0026lt;\u0026thinsp;0.05,**= p\u0026thinsp;\u0026lt;\u0026thinsp;0.00, ***= p\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The hydration level changes of the participant of within groups.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003e \u003cb\u003e****\u003c/b\u003e Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e \u003cb\u003eNere Here ****\u003c/b\u003e\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec17\" class=\"Section2\"\u003e \u003ch2\u003e3.3.Prefrontal hemodynamic changes\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThe prefrontal hemodynamic were assessed between group analyses before exercise. The results indicated that there was not a significant difference in Oxy-Hb (0.72\u0026thinsp;\u0026plusmn;\u0026thinsp;0.25/-0.19\u0026thinsp;\u0026plusmn;\u0026thinsp;0.56, p\u0026thinsp;=\u0026thinsp;0.080), Deoxy-Hb (-0.02\u0026thinsp;\u0026plusmn;\u0026thinsp;1.34/1.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.69, p\u0026thinsp;=\u0026thinsp;0.277), and Total-Hb (-0.11\u0026thinsp;\u0026plusmn;\u0026thinsp;1.87/-0.90\u0026thinsp;\u0026plusmn;\u0026thinsp;0.75, p\u0026thinsp;=\u0026thinsp;0.277) levels between the HBMIG and LBMIG groups before exercise. After exercise, there were also no significant differences in Oxy-Hb (-0.01\u0026thinsp;\u0026plusmn;\u0026thinsp;1.34/1.10\u0026thinsp;\u0026plusmn;\u0026thinsp;0.72, p\u0026thinsp;=\u0026thinsp;0.287), Deoxy-Hb (1.25\u0026thinsp;\u0026plusmn;\u0026thinsp;1.48/0.52\u0026thinsp;\u0026plusmn;\u0026thinsp;1.91, p\u0026thinsp;=\u0026thinsp;401) and Total-Hb (1.24\u0026thinsp;\u0026plusmn;\u0026thinsp;2.65/1.63\u0026thinsp;\u0026plusmn;\u0026thinsp;2.53, p\u0026thinsp;=\u0026thinsp;0.976) levels between the two groups. These results indicate that hemodynamic values changed over time before and after exercise. Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e presents changes in brain hemodynamic among all participants and groups.\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\u003eBrain hemodynamic results pre and post exercise sessions analysis.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"18\"\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 \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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c13\" colnum=\"13\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c14\" colnum=\"14\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c15\" colnum=\"15\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c16\" colnum=\"16\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c17\" colnum=\"17\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c18\" colnum=\"18\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"18\" nameend=\"c18\" namest=\"c1\"\u003e \u003cp\u003eBetween Group Analysis\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eStatus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e\u003cb\u003eValues\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003eStatus\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e\u003cb\u003eValues\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c12\" namest=\"c11\"\u003e \u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003e\u003cb\u003eStatus\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c18\" namest=\"c15\"\u003e \u003cp\u003e\u003cb\u003eValues P\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eHBMIG\u003c/p\u003e \u003cp\u003ePre\u003c/p\u003e \u003cp\u003eOxy-Hb\u003c/p\u003e \u003cp\u003e(mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e0.72\u0026thinsp;\u0026plusmn;\u0026thinsp;0.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e0.080\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003eHBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eDeoxy-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e-0.02\u0026thinsp;\u0026plusmn;\u0026thinsp;1.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c12\" namest=\"c11\" rowspan=\"2\"\u003e \u003cp\u003e0.277\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003e\u003cb\u003eHBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eTotal-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c16\" namest=\"c15\"\u003e \u003cp\u003e-0.11\u0026thinsp;\u0026plusmn;\u0026thinsp;1.87\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c18\" namest=\"c17\" rowspan=\"2\"\u003e \u003cp\u003e0.277\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eLBMIG\u003c/p\u003e \u003cp\u003ePre\u003c/p\u003e \u003cp\u003eOxy-Hb\u003c/p\u003e \u003cp\u003e(mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e-0.19\u0026thinsp;\u0026plusmn;\u0026thinsp;0.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003eLBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eDeoxy-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e1.09\u0026thinsp;\u0026plusmn;\u0026thinsp;0.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003e\u003cb\u003eLBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eTotal-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c16\" namest=\"c15\"\u003e \u003cp\u003e0.90\u0026thinsp;\u0026plusmn;\u0026thinsp;0.75\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eHBMIG\u003c/p\u003e \u003cp\u003ePost\u003c/p\u003e \u003cp\u003eOxy-Hb\u003c/p\u003e \u003cp\u003e(mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e-0.01\u0026thinsp;\u0026plusmn;\u0026thinsp;1.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e0.287\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003eHBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eDeoxy-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e1.25\u0026thinsp;\u0026plusmn;\u0026thinsp;1.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c12\" namest=\"c11\" rowspan=\"2\"\u003e \u003cp\u003e0.401\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003e\u003cb\u003eHBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eTotal-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c16\" namest=\"c15\"\u003e \u003cp\u003e1.24\u0026thinsp;\u0026plusmn;\u0026thinsp;2.65\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c18\" namest=\"c17\" rowspan=\"2\"\u003e \u003cp\u003e0.976\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eLBMIG\u003c/p\u003e \u003cp\u003ePost\u003c/p\u003e \u003cp\u003eOxy-Hb\u003c/p\u003e \u003cp\u003e(mmol/L)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e1.10\u0026thinsp;\u0026plusmn;\u0026thinsp;0.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003eLBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eDeoxy-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e0.52\u0026thinsp;\u0026plusmn;\u0026thinsp;1.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003e\u003cb\u003eLBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eTotal-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/L)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c16\" namest=\"c15\"\u003e \u003cp\u003e1.63\u0026thinsp;\u0026plusmn;\u0026thinsp;2.53\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"18\" nameend=\"c18\" namest=\"c1\"\u003e \u003cp\u003eWithin Group Analysis\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStatus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eExercise\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eOxy-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/mL)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eExercise\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eOxy-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/mL)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eExercise\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eDeoxy-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/mL)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eExercise\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eDeoxy-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/mL)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c13\" namest=\"c12\"\u003e \u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c15\" namest=\"c14\"\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eExercise\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eTotal-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/mL)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c17\" namest=\"c16\"\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eExercise\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eTotal-Hb\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003e(mmol/mL)\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c18\"\u003e \u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHBMIG\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e0.729\u0026thinsp;\u0026plusmn;\u0026thinsp;0.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003e-0.013\u0026thinsp;\u0026plusmn;\u0026thinsp;1.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.338\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e-0.028\u0026thinsp;\u0026plusmn;\u0026thinsp;1.34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003e1.259\u0026thinsp;\u0026plusmn;\u0026thinsp;1.48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c13\" namest=\"c12\"\u003e \u003cp\u003e\u003cb\u003e0.045*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c15\" namest=\"c14\"\u003e \u003cp\u003e-0.214\u0026thinsp;\u0026plusmn;\u0026thinsp;1.69\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c17\" namest=\"c16\"\u003e \u003cp\u003e1.246\u0026thinsp;\u0026plusmn;\u0026thinsp;2.5\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c18\"\u003e \u003cp\u003e\u003cb\u003e0.050*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLBMIG\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e-0.190\u0026thinsp;\u0026plusmn;\u0026thinsp;0.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003e1.106\u0026thinsp;\u0026plusmn;\u0026thinsp;0.72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003e0.028*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e1.092\u0026thinsp;\u0026plusmn;\u0026thinsp;0.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003e0.901\u0026thinsp;\u0026plusmn;\u0026thinsp;0.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c13\" namest=\"c12\"\u003e \u003cp\u003e0.382\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c15\" namest=\"c14\"\u003e \u003cp\u003e0.901\u0026thinsp;\u0026plusmn;\u0026thinsp;0.75\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c17\" namest=\"c16\"\u003e \u003cp\u003e1.634\u0026thinsp;\u0026plusmn;\u0026thinsp;2.53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c18\"\u003e \u003cp\u003e0.441\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eALL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e0.227\u0026thinsp;\u0026plusmn;\u0026thinsp;0.6\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003e0.307\u0026thinsp;\u0026plusmn;\u0026thinsp;1.2\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.877\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e0.313\u0026thinsp;\u0026plusmn;\u0026thinsp;1.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003e-0.155\u0026thinsp;\u0026plusmn;\u0026thinsp;1.91\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c13\" namest=\"c12\"\u003e \u003cp\u003e0.446\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c15\" namest=\"c14\"\u003e \u003cp\u003e0.541\u0026thinsp;\u0026plusmn;\u0026thinsp;1.10\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c17\" namest=\"c16\"\u003e \u003cp\u003e0.152\u0026thinsp;\u0026plusmn;\u0026thinsp;2.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c18\"\u003e \u003cp\u003e0.559\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eBrain hemodynamic levels were assessed within-group analysis in the study groups, and post-exercise Oxy-Hb (0.227\u0026thinsp;\u0026plusmn;\u0026thinsp;0.64/0.307\u0026thinsp;\u0026plusmn;\u0026thinsp;1.27, p\u0026thinsp;=\u0026thinsp;0.877), Deoxy-Hb (-0.313\u0026thinsp;\u0026plusmn;\u0026thinsp;1.253/-0.155\u0026thinsp;\u0026plusmn;\u0026thinsp;1.912, p\u0026thinsp;=\u0026thinsp;0.446), and Total-Hb (0.541\u0026thinsp;\u0026plusmn;\u0026thinsp;1.105/0.152\u0026thinsp;\u0026plusmn;\u0026thinsp;2.558, p\u0026thinsp;=\u0026thinsp;0.559) values (see Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). In the HBMIG group, an increase was observed in Deoxy-Hb (-0.028\u0026thinsp;\u0026plusmn;\u0026thinsp;1.342/-1.259\u0026thinsp;\u0026plusmn;\u0026thinsp;1.485, p\u0026thinsp;=\u0026thinsp;0.045) and Total-Hb (-0.214\u0026thinsp;\u0026plusmn;\u0026thinsp;1.697/1.246\u0026thinsp;\u0026plusmn;\u0026thinsp;2.53, p\u0026thinsp;=\u0026thinsp;0.050). Oxy-Hb (0.729\u0026thinsp;\u0026plusmn;\u0026thinsp;0.252/-0.013\u0026thinsp;\u0026plusmn;\u0026thinsp;1.349, p\u0026thinsp;=\u0026thinsp;0.338) values did not show any significant changes. In the LBMIG group, an increase in Oxy-Hb (-0.190\u0026thinsp;\u0026plusmn;\u0026thinsp;0.564/1.106\u0026thinsp;\u0026plusmn;\u0026thinsp;0.724, p\u0026thinsp;=\u0026thinsp;0.028) was observed; no significant changes were observed in Deoxy-Hb (1.092\u0026thinsp;\u0026plusmn;\u0026thinsp;0.528/0.901\u0026thinsp;\u0026plusmn;\u0026thinsp;0.752, p\u0026thinsp;=\u0026thinsp;0.382) and total-Hb (0.901\u0026thinsp;\u0026plusmn;\u0026thinsp;0.752/1.634\u0026thinsp;\u0026plusmn;\u0026thinsp;2.536, p\u0026thinsp;=\u0026thinsp;0.441) values.\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e. Brain hemodynamic results pre and post exercise sessions analysis.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003e \u003cb\u003e****\u003c/b\u003e Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e \u003cb\u003eNere Here ****\u003c/b\u003e\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec18\" class=\"Section2\"\u003e \u003ch2\u003e3.4.Cognitive Response related to exercise\u003c/h2\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eCognitive responses were evaluated between groups before exercise. The results indicated that the Correct Answers (18.33\u0026thinsp;\u0026plusmn;\u0026thinsp;4.45/22.50\u0026thinsp;\u0026plusmn;\u0026thinsp;6.92, p\u0026thinsp;=\u0026thinsp;0.375), Correct Answers Reaction Time (RT) (492.50\u0026thinsp;\u0026plusmn;\u0026thinsp;30.48/543.69\u0026thinsp;\u0026plusmn;\u0026thinsp;98.72, p\u0026thinsp;=\u0026thinsp;0.286), Wrong Answers (3.33\u0026thinsp;\u0026plusmn;\u0026thinsp;1.40/6.66\u0026thinsp;\u0026plusmn;\u0026thinsp;5.92, p\u0026thinsp;=\u0026thinsp;0.354), Wrong Answers RT (641.33\u0026thinsp;\u0026plusmn;\u0026thinsp;112.32/580.14\u0026thinsp;\u0026plusmn;\u0026thinsp;64.92, p\u0026thinsp;=\u0026thinsp;0.308) and Missed Answers (22.33\u0026thinsp;\u0026plusmn;\u0026thinsp;4.96/17.50\u0026thinsp;\u0026plusmn;\u0026thinsp;6.89, p\u0026thinsp;=\u0026thinsp;0.314) counts did not show a significant difference. After exercise, a significant decrease was observed in the number of missed answers (22.33\u0026thinsp;\u0026plusmn;\u0026thinsp;5.60/13.66\u0026thinsp;\u0026plusmn;\u0026thinsp;3.67, p\u0026thinsp;=\u0026thinsp;0.013) (see Fig.\u0026nbsp;2), while there was no significant difference in the number of correct answers (16.00\u0026thinsp;\u0026plusmn;\u0026thinsp;6.06/23.50\u0026thinsp;\u0026plusmn;\u0026thinsp;7.50, p\u0026thinsp;=\u0026thinsp;0.106), correct answers reaction time (RT) (492.89\u0026thinsp;\u0026plusmn;\u0026thinsp;95.72/539.57\u0026thinsp;\u0026plusmn;\u0026thinsp;73.66, p\u0026thinsp;=\u0026thinsp;0.236), wrong answers (6.16\u0026thinsp;\u0026plusmn;\u0026thinsp;2.61/4.33\u0026thinsp;\u0026plusmn;\u0026thinsp;3.07, p\u0026thinsp;=\u0026thinsp;0.576), and wrong answers RT (574.13\u0026thinsp;\u0026plusmn;\u0026thinsp;177.40/630.92\u0026thinsp;\u0026plusmn;\u0026thinsp;200.42, p\u0026thinsp;=\u0026thinsp;0.626). Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e shows the changes among all participants and groups.\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\u003eCognitive response of related to exercise.\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"18\"\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 \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 \u003cdiv align=\"left\" class=\"colspec\" colname=\"c11\" colnum=\"11\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c12\" colnum=\"12\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c13\" colnum=\"13\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c14\" colnum=\"14\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c15\" colnum=\"15\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c16\" colnum=\"16\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c17\" colnum=\"17\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c18\" colnum=\"18\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"18\" nameend=\"c18\" namest=\"c1\"\u003e \u003cp\u003eBetween Group Analysis\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eStatus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003eValues\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003eStatus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003eValues\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c12\" namest=\"c11\"\u003e \u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003eStatus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c18\" namest=\"c15\"\u003e \u003cp\u003eValues \u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eHBMIG\u003c/p\u003e \u003cp\u003ePre\u003c/p\u003e \u003cp\u003eCorrect\u003c/p\u003e \u003cp\u003eAnswer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e18.33\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e4.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e0.375\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003eHBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eWrong\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e3.33\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e1.40\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c12\" namest=\"c11\" rowspan=\"2\"\u003e \u003cp\u003e0.354\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003e\u003cb\u003eHBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eMiss\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c16\" namest=\"c15\"\u003e \u003cp\u003e22.33\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e4.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c18\" namest=\"c17\" rowspan=\"2\"\u003e \u003cp\u003e0.314\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eLBMIG\u003c/p\u003e \u003cp\u003ePre\u003c/p\u003e \u003cp\u003eCorrect\u003c/p\u003e \u003cp\u003eAnswer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e22.50\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e6.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003eLBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eWrong\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e6.66\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e5.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003e\u003cb\u003eLBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eMiss\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c16\" namest=\"c15\"\u003e \u003cp\u003e17.50\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e6.89\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eHBMIG\u003c/p\u003e \u003cp\u003ePost\u003c/p\u003e \u003cp\u003eCorrect\u003c/p\u003e \u003cp\u003eAnswer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e16.00\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e6.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003e0.106\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003eHBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eWrong\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e6.16\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e2.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c12\" namest=\"c11\" rowspan=\"2\"\u003e \u003cp\u003e0.576\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003e\u003cb\u003eHBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eMiss\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c16\" namest=\"c15\"\u003e \u003cp\u003e23.33\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e5.60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" morerows=\"1\" nameend=\"c18\" namest=\"c17\" rowspan=\"2\"\u003e \u003cp\u003e\u003cb\u003e0.013*\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003eLBMIG\u003c/p\u003e \u003cp\u003ePost\u003c/p\u003e \u003cp\u003eCorrect\u003c/p\u003e \u003cp\u003eAnswer\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c4\" namest=\"c3\"\u003e \u003cp\u003e23.50\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e7.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c8\" namest=\"c6\"\u003e \u003cp\u003e\u003cb\u003eLBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eWrong\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c10\" namest=\"c9\"\u003e \u003cp\u003e4.33\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e3.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c14\" namest=\"c13\"\u003e \u003cp\u003e\u003cb\u003eLBMIG\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eMiss\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c16\" namest=\"c15\"\u003e \u003cp\u003e13.66\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e3.67\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"18\" nameend=\"c18\" namest=\"c1\"\u003e \u003cp\u003eWithin Group Analysis\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStatus\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eCorrect\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eCorrect\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eWrong\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eWrong\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c13\" namest=\"c12\"\u003e \u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c15\" namest=\"c14\"\u003e \u003cp\u003e\u003cb\u003ePre\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eMiss\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c17\" namest=\"c16\"\u003e \u003cp\u003e\u003cb\u003ePost\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eWrong\u003c/b\u003e\u003c/p\u003e \u003cp\u003e\u003cb\u003eAnswer\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c18\"\u003e \u003cp\u003e\u003cb\u003ep\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHBMIG\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e18.33\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e4.45\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003e16.00\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e6.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.376\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e3.33\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e2.33\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003e6.16\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e2.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c13\" namest=\"c12\"\u003e \u003cp\u003e0.133\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c15\" namest=\"c14\"\u003e \u003cp\u003e22.33\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e4.96\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c17\" namest=\"c16\"\u003e \u003cp\u003e23.33\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e5.61\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c18\"\u003e \u003cp\u003e0.658\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eLBMIG\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e22.50\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e6.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003e23.50\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e7.50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.727\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e6.66\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e5.92\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003e4.33\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e3.07\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c13\" namest=\"c12\"\u003e \u003cp\u003e0.428\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c15\" namest=\"c14\"\u003e \u003cp\u003e17.50\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e6.89\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c17\" namest=\"c16\"\u003e \u003cp\u003e13.66\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e3.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c18\"\u003e \u003cp\u003e0.471\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eALL\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c3\" namest=\"c2\"\u003e \u003cp\u003e20.41\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e5.94\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"3\" nameend=\"c6\" namest=\"c4\"\u003e \u003cp\u003e19.75\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e7.59\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c7\"\u003e \u003cp\u003e0.718\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c9\" namest=\"c8\"\u003e \u003cp\u003e5.00\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e4.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c11\" namest=\"c10\"\u003e \u003cp\u003e5.35\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e4.88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c13\" namest=\"c12\"\u003e \u003cp\u003e0.885\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c15\" namest=\"c14\"\u003e \u003cp\u003e19.91\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e6.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c17\" namest=\"c16\"\u003e \u003cp\u003e19.08\u003c/p\u003e \u003cp\u003e\u0026plusmn;\u003c/p\u003e \u003cp\u003e6.93\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c18\"\u003e \u003cp\u003e0.535\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"18\"\u003eNote: HBMIG= High BMI Group, LBMIG\u0026thinsp;=\u0026thinsp;Low BMI Group, ALL\u0026thinsp;=\u0026thinsp;All Participants, p\u0026thinsp;=\u0026thinsp;Pre-Post Test Statistical Difference: *= p\u0026thinsp;\u0026lt;\u0026thinsp;0.05, **= p\u0026thinsp;\u0026lt;\u0026thinsp;0.00, ***= p\u0026thinsp;\u0026lt;\u0026thinsp;0.001\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eCognitive answers were assessed within group analysis in the study groups and post-exercise. The Correct Answer (20.41\u0026thinsp;\u0026plusmn;\u0026thinsp;5.94/19.75\u0026thinsp;\u0026plusmn;\u0026thinsp;7.59, p\u0026thinsp;=\u0026thinsp;0.718), the Correct Answer RT (518.10\u0026thinsp;\u0026plusmn;\u0026thinsp;74.61/516.23\u0026thinsp;\u0026plusmn;\u0026thinsp;85.01, p\u0026thinsp;=\u0026thinsp;0.926), the Wrong Answer (5.00\u0026thinsp;\u0026plusmn;\u0026thinsp;4.93/5.35\u0026thinsp;\u0026plusmn;\u0026thinsp;4.88, p\u0026thinsp;=\u0026thinsp;0.885), the Wrong Answer RT (610.76\u0026thinsp;\u0026plusmn;\u0026thinsp;93.12/602.52\u0026thinsp;\u0026plusmn;\u0026thinsp;182.87, p\u0026thinsp;=\u0026thinsp;0.857), and the Miss Answer (19.91\u0026thinsp;\u0026plusmn;\u0026thinsp;6.25/19.08\u0026thinsp;\u0026plusmn;\u0026thinsp;6.93, p\u0026thinsp;=\u0026thinsp;0.535) values are not statistical differences. The HBMIG group, the Correct Answer (18.33\u0026thinsp;\u0026plusmn;\u0026thinsp;4.45/16.00\u0026thinsp;\u0026plusmn;\u0026thinsp;6.06, p\u0026thinsp;=\u0026thinsp;0.376), the Correct Answer RT (492.50\u0026thinsp;\u0026plusmn;\u0026thinsp;30.48/492.89\u0026thinsp;\u0026plusmn;\u0026thinsp;95.72, p\u0026thinsp;=\u0026thinsp;0.990), the Wrong Answer (3.33\u0026thinsp;\u0026plusmn;\u0026thinsp;2.33/6.16\u0026thinsp;\u0026plusmn;\u0026thinsp;2.61, p\u0026thinsp;=\u0026thinsp;0.133), the Wrong Answer RT (641.33\u0026thinsp;\u0026plusmn;\u0026thinsp;113.32/574.132\u0026thinsp;\u0026plusmn;\u0026thinsp;177.40, p\u0026thinsp;=\u0026thinsp;0.279), and the Miss Answer (22.33\u0026thinsp;\u0026plusmn;\u0026thinsp;4.96/23.33\u0026thinsp;\u0026plusmn;\u0026thinsp;5.61, p\u0026thinsp;=\u0026thinsp;0.885) values are not statistical differences. In the LBMIG group, the Correct Answer (22.50\u0026thinsp;\u0026plusmn;\u0026thinsp;6.92/23.50\u0026thinsp;\u0026plusmn;\u0026thinsp;7.50, p\u0026thinsp;=\u0026thinsp;0.727), the Correct Answer RT (543.69\u0026thinsp;\u0026plusmn;\u0026thinsp;98.72/630.92\u0026thinsp;\u0026plusmn;\u0026thinsp;200.42, p\u0026thinsp;=\u0026thinsp;0.893), the Wrong Answer (6.66\u0026thinsp;\u0026plusmn;\u0026thinsp;5.92/4.33\u0026thinsp;\u0026plusmn;\u0026thinsp;3.07, p\u0026thinsp;=\u0026thinsp;0.428), the Wrong Answer RT (580.14\u0026thinsp;\u0026plusmn;\u0026thinsp;64.92/630.92\u0026thinsp;\u0026plusmn;\u0026thinsp;200.42, p\u0026thinsp;=\u0026thinsp;0.471), and the Miss Answer (17.50\u0026thinsp;\u0026plusmn;\u0026thinsp;6.89/13.66\u0026thinsp;\u0026plusmn;\u0026thinsp;3.67, p\u0026thinsp;=\u0026thinsp;0.471) values are not statistical differences (see Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. Cognitive response of related to exercise.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003e \u003cb\u003e****\u003c/b\u003e Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e \u003cb\u003eNere Here ****\u003c/b\u003e\u003c/p\u003e \u003cp\u003e \u003cb\u003e**** Fig.\u0026nbsp;2 Nere Here ****\u003c/b\u003e \u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003cstrong\u003eNote\u003c/strong\u003e \u003cp\u003eThe light-colored column represents HBMIG data, while the dark-colored column represents LBMIG data.\u003c/p\u003e \u003c/p\u003e \u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003e \u003cb\u003eFigure 2.\u003c/b\u003e All group Post Exercise Cognitive Response.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eThis study investigates the effect of body mass index on prefrontal cortex hemodynamic and cognitive functions in exercise-induced hypohydration in male athletes. The main finding of the study was that oxyhemoglobin values increased significantly in cognitive tasks during exercise-related hypohydration conditions in the LBMIG, while deoxyhemoglobin values increased significantly in the HBMIG. Therefore, missing answers increased significantly in the HBMIG cognitive test results.\u003c/p\u003e \u003cp\u003eThe changes in body weight and hematocrit following the hypohydration condition created in our study are like those observed in participant groups with similar BMI levels in studies conducted under laboratory and real field conditions in the literature [\u003cspan additionalcitationids=\"CR58\" citationid=\"CR57\" class=\"CitationRef\"\u003e57\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR59\" class=\"CitationRef\"\u003e59\u003c/span\u003e]. Specifically, hypohydration effects are noticeable in studies with long-interval exercise. Juett et al. induced a body weight loss of 1% using the Loughborough shuttle run (15x6 min/2 min rest between sit-ups) in 14 active male athletes with a BMI of 23.6\u0026thinsp;\u0026plusmn;\u0026thinsp;2.6 kg/m\u0026sup2; [\u003cspan citationid=\"CR58\" class=\"CitationRef\"\u003e58\u003c/span\u003e]. James et al. evaluated the performance of nine healthy participants in intermittent exercise (8x10 min cycle/5 min rest) followed by 15 min time trial cycling. At the end of the study, the participants had lost\u0026thinsp;~\u0026thinsp;1.5% of their body weight [\u003cspan citationid=\"CR57\" class=\"CitationRef\"\u003e57\u003c/span\u003e]. Brun et al. observed the effects of 30 minutes of submaximal exercise on hematocrit values. They observed an increase in hematocrit values taken immediately after exercise. This change is in line with the results of our study [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAs a result of the study, the oxyhemoglobin values of the participants in the LBMIG increased significantly during the cognitive task under the EIH. It has been reported in the literature that physically fit athletes exhibit chronic adaptations in exercise-induced forebrain hemodynamic responses and work more efficiently [\u003cspan citationid=\"CR60\" class=\"CitationRef\"\u003e60\u003c/span\u003e]. Kim et al. performed a 2-back task on 16 healthy men before and after 10 minutes of moderate and high-intensity aerobic exercise. Participants' performance on the 2-back task allowed assessment of hemodynamic changes in the prefrontal cortex. At the end of the study, they reported that during the 2-back test, an oxyhemoglobin increase in the dorsolateral prefrontal cortex was observed under moderate and high-intensity exercise conditions [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Oxyhemoglobin level is considered an indicator of increased neuronal workload. This increase in pre- and post-exercise oxyhemoglobin levels may be an indicator of increased neuronal efficiency in the LBMIG due to the beneficial effects of exercise. In particular, the fact that local microcirculation is not impaired despite the increased workload on the forebrain during the cognitive task may indicate that the LBMIG endures hypohydration conditions. This interpretation supports the finding that cognitive test results were not adversely affected in the LBMIG.\u003c/p\u003e \u003cp\u003eOur study found that deoxyhemoglobin levels increased significantly during cognitive tasks in HBMIG participants under EIH conditions. This response may indicate a poorer neurovascular match to similar cognitive loads under EIH conditions. This finding is supported by significantly increased miss scores in cognitive tasks. Our unique study design has resulted in the absence of any comparable studies conducted under similar conditions. This finding has been discussed in the context of BMI levels, stress, cognition, and brain responses. In the literature, Jones et al. evaluated the activity of the dorsolateral prefrontal cortex in overweight adults (body mass index: 28.56\u0026thinsp;\u0026plusmn;\u0026thinsp;4.95 kg/m\u0026sup2;) after 15 minutes of cycling exercise. They reported higher dorsolateral prefrontal cortex activity immediately post-exercise [\u003cspan citationid=\"CR60\" class=\"CitationRef\"\u003e60\u003c/span\u003e]. Soares et al. non-invasively assessed differences in oxidative metabolism in overweight compared to normal-weight individuals in normal-weight and overweight subjects using near-infrared spectroscopy and the occlusion stress. It has been reported that an increase in deoxyhemoglobin levels occurs when blood flow is restricted in people who are overweight [\u003cspan citationid=\"CR61\" class=\"CitationRef\"\u003e61\u003c/span\u003e]. From a cognitive perspective, a study conducted on a large group of young participants found a negative correlation between BMI and general cognitive abilities [\u003cspan citationid=\"CR62\" class=\"CitationRef\"\u003e62\u003c/span\u003e]. Considering the results of our HBMIG participants and the literature presented, it is believed that high BMI values cause the hemodynamic responses of the forebrain and executive function to be more vulnerable and prone to impairment under physical and cognitive stress.\u003c/p\u003e \u003cp\u003eBased on cognitive test results in the EIH condition after prolonged exercise, no significant change was found in the number of correct answers (Δ = +1), wrong answers (Δ = +2.33), or missing answers (Δ = -3.84) in the LBMIG, indicating that cognitive performance was maintained, and no deterioration occurred. On the other hand, while a numerical increase in missing answers (Δ = +1) was observed in HBMIG, a numerical decrease in the number of correct answers (Δ = -2.33) and a numerical increase in the number of wrong answers (Δ = +2.83) were observed. In the between-group comparison, HBMIG missing answers increased significantly in the EIH condition compared to LBMIG (p\u0026thinsp;=\u0026thinsp;0.013). There are hardly any studies in the literature investigating the effects of prolonged exercise on cognition. Executive functions and exercise duration have a significant functional link, particularly in prolonged exercise [\u003cspan additionalcitationids=\"CR64\" citationid=\"CR63\" class=\"CitationRef\"\u003e63\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR65\" class=\"CitationRef\"\u003e65\u003c/span\u003e]. Tempest et al. evaluated the effect of 60 minutes of low-load, prolonged exercise on cognitive function using the 2-back task with 14 participants. They found only an increase in the number of correct answers, with no change in other responses [\u003cspan citationid=\"CR66\" class=\"CitationRef\"\u003e66\u003c/span\u003e]. This finding is consistent with the results of the only LBMIG in our study. In addition, studies in the literature on exercise intensity and cognition have shown significant changes in the number of correct and wrong responses as well as the number of missed serial responses at moderate and high-intensity exercises in fit athletes [\u003cspan citationid=\"CR65\" class=\"CitationRef\"\u003e65\u003c/span\u003e, \u003cspan citationid=\"CR66\" class=\"CitationRef\"\u003e66\u003c/span\u003e]. In more detail, Cantelon et al.'s comprehensive review study found that incremental exercise from very low to moderate levels could lead to minor enhancements in working memory [\u003cspan citationid=\"CR63\" class=\"CitationRef\"\u003e63\u003c/span\u003e]. In our study, we observed that 30 minutes of aerobic exercise followed by 15 minutes of high-intensity interval exercise had a protective effect on executive functions in the LBMIG and a negative effect on the HBMIG in the 2-back condition. This information may indicate that BMI is a parameter that affects cognitive function during prolonged exercise.\u003c/p\u003e \u003cp\u003eIn our research, the high-intensity interval model following constant load exercise had a detrimental impact on cognitive function in individuals with a high BMI. As a possible physiological mechanism for this result obtained in our study, exercise maintenance with fluid deprivation in the HBMIG may have increased resource utilization during the mental task, consequently increasing the resource consumption observed during cognitive tasks and the inability of HBMI groups to maintain task continuity by taking involuntary breaks (missing value). Future studies are needed to investigate the effects of exercise on cognition based on neurophysiological factors in different populations (gender, age, BMI) and conditions (dehydration, cold, heat, humidity, etc.).\u003c/p\u003e \u003cp\u003e \u003cem\u003eLimitation\u003c/em\u003e \u003c/p\u003e \u003cp\u003eDue to the thermodynamic effects immediately following exercise, fluid loss continued, contributing to dehydration as measured. Unfortunately, the assessment did not include this aspect of fluid loss. Future studies should aim for more profound investigations with larger participant groups. Nevertheless, we believe our findings will be valuable in drawing attention to the issue. In addition, our group consisted of athletes actively competing in national and international leagues and due to the circumstances related to COVID-19, it was difficult to reach a larger number of athletes, leading to low sample sizes for both groups. Therefore, a larger sample size (if possible) should be used in further studies to confirm, refute, and/or extend our findings.\u003c/p\u003e \u003c/div\u003e \u003c/p\u003e"},{"header":"5. Conclusions","content":"\u003cp\u003e \u003cdiv class=\"BlockQuote\"\u003e \u003cp\u003eExercise-induced hypohydration had a detrimental impact on prefrontal cortexoxygenation and cognitive functions, particularly in athletes with a high BMI. On the other hand, athletes with low BMI values who participated in our study demonstrated higher neural efficiency and stable cognitive performance under physical stress. These results may highlight that athletes with high BMI values who participate in sports requiring high physical exertion and executive function-based cognitive skills should be more careful about exercise-induced dehydration conditions.\u003c/p\u003e \u003cp\u003ePractical Applications\u003c/p\u003e \u003cp\u003eIndividual plans tailored to athletes with high BMI values are necessary to prevent exercise-induced dehydration. Sports field staff and experts should monitor the amount of fluid and electrolytes lost by athletes during matches or training sessions. Environmental factors like heat, cold, and humidity should be carefully considered in this monitoring. Sports with high cognitive demands should prioritize addressing this issue.\u003c/p\u003e \u003cp\u003eWe recommend \u0026lsquo;awareness education\u0026rsquo; on the cognitive and physiological adverse effects of dehydration in athletes with high BMI values.\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\u003cp\u003eBMI\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Body Mass Index\u003c/p\u003e\n\u003cp\u003eLBMIG\u0026nbsp;\u0026nbsp;Low BMI Group\u003c/p\u003e\n\u003cp\u003eHBMIG\u0026nbsp;Heigh BMI Group\u003c/p\u003e\n\u003cp\u003eEIH\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Exercise-Induced Hypohydration\u003c/p\u003e\n\u003cp\u003ePFC\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Prefrontal Cortex (PFC),\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSMA\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Supplementary Motor Area\u003c/p\u003e\n\u003cp\u003efNIRS\u0026nbsp; \u0026nbsp;\u0026nbsp;Functional Near-Infrared Spectroscopy\u003c/p\u003e\n\u003cp\u003eOxy-Hb \u0026nbsp;Oxygenated Brain Tissue \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDeoxy-Hb \u0026nbsp;Deoxygenated Hemoglobin\u003c/p\u003e\n\u003cp\u003eBW\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;\u0026nbsp;Body Weight\u003c/p\u003e\n\u003cp\u003eHct\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Hematocrit\u003c/p\u003e\n\u003cp\u003eSIT\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;Sprint Interval Training\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAuthor Contributions:\u003c/strong\u003e Conceptualization, E.G and E.U; methodology, C.B., E.U., E.M., C.G., E.G.; formal analysis, E.U.,C.G. and E.G.; investigation, C.B. E.U.,E.G.,C.G. and E.M.; writing—original draft preparation, E.U., E.G., C.G., E.M., C.B. ; writing—review and editing, E.U., E.G., C.G., E.M., supervision, E.G. All authors have read and agreed to the published version of the manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding:\u003c/strong\u003e This research received no external funding\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInstitutional Review Board Statement:\u0026nbsp;\u003c/strong\u003eThis study was reviewed by the Dokuz Eylül University Non-Invasive Research Ethics Committee and approved by decision no. 2020/07-28 dated 13 April 2020 and was conducted in accordance with the Helsinki Declaration.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInformed Consent Statement:\u0026nbsp;\u003c/strong\u003eWritten informed consent to participate in this study was provided by the participant’s legal guardian/next of kin. Informed consent was obtained from all individual participants included in the study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability Statement:\u003c/strong\u003e All collected data in the current study are available after obtaining permission from all the authors. Written proposals can be addressed to the corresponding authors for appropriateness of use. The data are not publicly available due to privacy and ethical reasons.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of Interest:\u003c/strong\u003e The authors declare no conflicts of interest\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eUylas E, Zengin N, Futsi D, et al. Effects of exercise-induced hypohydration on human athletic performance, cognitive functions and brain hemodynamics: systematic mini review. Sport Sci Health. Published online July 22, 2025. https://doi.org/10.1007/s11332-025-01503-w \u003c/li\u003e\n\u003cli\u003eKim S, Kim Y, Park SM. 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Neural Plast. 2019;2019:8608317. https://doi.org/10.1155/2019/8608317\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-neuroscience","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"nros","sideBox":"Learn more about [BMC Neuroscience](http://bmcneurosci.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/nros/default.aspx","title":"BMC Neuroscience","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Submaximal Exercise, Exercise-Induced Hypohydration, Prefrontal Cortex Hemodynamics, Cognitive Functions, BMI","lastPublishedDoi":"10.21203/rs.3.rs-8820751/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8820751/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eObjectives:\u003c/strong\u003e This study examines the impact of exercise-induced hypohydration on prefrontal hemodynamic and cognitive functions within high and low body mass index athletes.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMethods: \u003c/strong\u003eA total of twelve athletes well adapted to the bicycle ergometer were included in the study (LBMIG (24.64 kg/m²) and HBMIG (32.45 kg/m²)). Participants attended two visits to the laboratory. At their first visit, their body weight and hemocrit values were assembled, and they completed the practice 2-back test. At their second visit, participants' body weights and hematocrit values were measured, followed by recording their 2-back performance and prefrontal hemodynamic responses during performance. This session was followed by submaximal exercise and then 4x20 seconds of sprint intervals. Afterward, 2-back test performance was measured with their prefrontal hemodynamic responses.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eHematocrit levels increased in both groups compared to pre-exercise levels (p\u0026lt; 0.05), with a higher increase in the HBMIG (p=0.045). On the other hand, pre-post exercise responses in prefrontal hemodynamic activity during the 2-back test showed different patterns for each group: an increase in oxyhemoglobin for the LBMIG (p=0.002), an increase in deoxyhemoglobin for the HBMIG (p=0.033), and an increase in total hemoglobin for the HBMIG (p=0.050). Furthermore, the number of missing answers in the post-exercise 2-back test results was significantly higher in the HBMI group compared to the LBMI group.\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusions: \u003c/strong\u003eExercise-induced hypohydration may negatively affects prefrontal hemodynamics and cognitive function in high-BMI athletes. This effect may cause cognitive decline in athletes with high BMI values, negatively affecting their sport or match performance under physical fatigue.\u003c/p\u003e","manuscriptTitle":"The Effect of Body Mass Index on Prefrontal Cortex Hemodynamic and Cognitive Functions In Exercise-Induced Hypohydration in Male Athletes","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-02-24 16:38:55","doi":"10.21203/rs.3.rs-8820751/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"editorInvitedReview","content":"","date":"2026-03-02T12:53:15+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"102496613430123875362008236107707196607","date":"2026-03-02T09:49:45+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-02-19T20:26:19+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-02-11T14:38:47+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-02-10T12:20:37+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-02-10T12:14:35+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Neuroscience","date":"2026-02-08T09:49:14+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-neuroscience","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"nros","sideBox":"Learn more about [BMC Neuroscience](http://bmcneurosci.biomedcentral.com/)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/nros/default.aspx","title":"BMC Neuroscience","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"60841d81-c94d-4ebe-8dc7-a0778200457e","owner":[],"postedDate":"February 24th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-02-24T16:38:55+00:00","versionOfRecord":[],"versionCreatedAt":"2026-02-24 16:38:55","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-8820751","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8820751","identity":"rs-8820751","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}