Benefits of exercising with others on physical and mental health in Japan: understanding the underlying mechanisms

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However, evidence regarding physical health outcomes and younger populations in Japan remains limited. This study aimed to examine whether exercising with others is associated with better physical and subjective health among Japanese adults and to assess the mediating roles of social interaction and exercise habits. Methods : This study analysed cross-sectional data from 28,680 Japanese adults (mean age = 50.2 years) who participated in the 2022 nationwide sports participation survey. Participants were classified into four groups: non-exercising, exercising alone, exercising with others, and mixed-type (both alone and with others). Logistic regression was used to assess associations between exercise type and health outcomes including underweight (body mass index < 18.5 kg/m²), obesity (body mass index ≥ 25 kg/m²), and subjective health, adjusting for demographic variables. Mediation analyses evaluated indirect effects via social interaction and exercise habits. Results Compared with exercising alone, exercising with others was associated with lower odds of being underweight and higher odds of reporting good subjective health. Similar trends were observed for mixed-type exercisers. No significant association was found with obesity. Mediation analyses revealed small but significant indirect effects on subjective health through social interaction, while direct effects remained substantial. Conclusions Exercising with others is linked to improved subjective health and reduced risk of underweight among Japanese adults, partially mediated by social and behavioural factors. Promoting group-based exercise may be an effective public health strategy in Japan. Social interaction Mediation analysis Subjective health body mass index Japan Introduction Title : Benefits of exercising with others on physical and mental health in Japan: understanding the underlying mechanisms Low physical activity poses various health challenges, including increased risk of lifestyle-related diseases and weakened immune function [ 1 , 2 ]. In Japan, only 33.5% of men and 31.5% of women engage in regular exercise. Among working-age individuals in their 20s–40s, these numbers decrease further to 21.1% for men and 20.4% for women [ 3 ], falling short of the national targets (36.0% for men, 33.0% for women) [ 4 ]. Conditions associated with physical inactivity account for approximately one-third of medical expenses among those aged ≥ 65 years in Japan [ 5 ], and the economic burden extends beyond medical costs to include productivity losses owing to health-related absenteeism [ 6 ]. Additionally, individuals who are physically inactive during their youth are more likely to experience a decline in work capacity as adults [ 7 ], emphasising the importance of early preventive interventions. In parallel, another unique public health concern in Japan is the high prevalence of underweight among young women. Approximately 20% of women in their 20s are underweight, a figure comparable to that observed in low- and middle-income countries and higher than that in other developed nations [ 3 , 8 ]. Although obesity is widely recognised as a risk factor for chronic diseases, being underweight also carries significant health risks, including nutritional deficiencies and osteoporosis [ 9 ]. Addressing underweight among young women in Japan requires a dual approach: improving both dietary intake and physical activity [ 10 ]. Regular exercise may play a key role not only in preventing excessive weight loss but also in promoting overall metabolic health, suggesting that physical activity promotion can contribute to resolving underweight-related health risks [ 11 , 12 ]. In efforts to promote health benefits, growing attention has been paid to the role of social interaction in exercise settings. Although the underlying mechanisms through which physical activity promotes health remain a subject of ongoing research, an emerging hypothesis suggests that exercising with others yields greater health benefits than exercising alone [ 13 , 14 ]. Social interaction during physical activity may contribute to psychological well-being by facilitating communication, mutual encouragement, and shared experiences [ 15 ]. Moreover, participation in group-based exercise is associated with the formation of supportive social networks, which may help sustain long-term health behaviours [ 16 ]. The benefits of social interaction through exercise are not limited to mental health; strengthened social connectedness, social support, and peer bonding are associated with favourable physical health outcomes, including reduced mortality rates and decreased risk of chronic diseases [ 17 ]. In addition to these social and behavioural explanations, some researchers have drawn on psychological theories to better understand the mechanisms underlying these effects. One such framework is the self-determination theory (SDT), which identifies three basic psychological needs—autonomy, competence, and relatedness—as essential for promoting motivation and well-being [ 18 ]. Group-based exercise may contribute to fulfilling these needs, especially relatedness, thereby enhancing intrinsic motivation and increasing adherence to physical activity. Several studies have empirically demonstrated the health benefits of exercising with others. For example, large-scale Japanese studies focusing on older adults have shown that social exercise is associated with better subjective health and greater physical activity levels, even after accounting for exercise frequency [ 17 , 19 ]. However, such evidence is largely limited to the older population, and research involving younger generations in Japan remains lacking, despite growing concerns about physical inactivity among this demographic. Furthermore, most existing studies have primarily examined mental health outcomes, with limited investigations into how social exercise may affect physical health through psychosocial mechanisms. Addressing these research gaps is essential to designing effective and inclusive interventions for different age groups. Building on previous findings, two theoretical pathways have been proposed to explain how exercising with others contributes to improved health outcomes. The first highlights the role of social networks and interpersonal connections developed through group-based physical activities. Such interactions can foster emotional support, a sense of belonging, and enhanced motivation to continue exercising [ 20 ]. The second pathway emphasises behavioural engagement: exercising with others may increase accountability and consistency in physical activity owing to mutual expectations and social norms [ 21 ]. Drawing on these mechanisms, the present study aimed to clarify how exercising with others contributes to better health outcomes among Japanese adults. Specifically, this study examined the following two research questions: (1) Do Japanese adults who exercise with others report better health outcomes than those who exercise alone? and (2) To what extent are these associations mediated by increased social interaction and higher exercise volume? To address these questions, this study examined body mass index (BMI) and subjective health as health indicators and performed mediation analysis to clarify the psychological and behavioural mechanisms linking social exercise to health. This study contributes to the literature by examining both subjective and objective health outcomes in relation to social exercise and by employing mediation analysis to clarify the psychological and behavioural pathways through which exercising with others may exert health-promoting effects. In doing so, it offers valuable insights into the development of evidence-based interventions and health promotion policies targeting diverse age groups and addressing Japan’s unique public health challenges. Methods Materials This study used cross-sectional data from a nationwide survey on public awareness of sports participation in Japan conducted by the Japan Sports Agency from 7 to 27 December 2022 [ 22 ]. A total of 40,000 individuals aged 18–79 years were selected through stratified and random sampling strategies based on age, sex, and region to ensure representativeness of the Japanese adult population. In the study, 11,320 respondents were excluded based on the following criteria: (1) having a disability certificate, being bedridden, being unable to exercise in the past year, or being advised by a physician to refrain from physical activity (n = 1,973) and (2) selecting ‘Do not want to answer’ or ‘Not sure’ for any key demographic or health-related questions (n = 9,347). The final analytical sample comprised 28,680 individuals (15,045 men [52.5%] and 13,635 women [47.5%]), with a mean age of 50.2 years (standard deviation = 16.3). Measurements Exercise arrangement The participants were first asked whether they had engaged in any of the 60 listed types of exercise or sports over the past year. Individuals were classified as exercise participants if they selected at least one of the 58 activity options, excluding ‘have not exercised or played sports in the past year’ and ‘not sure’. They were instructed to exclude exercises performed as part of school education or employment but to include home-based activities (e.g. via online platforms or television). Participants who reported exercising were then asked how they usually engaged in these activities. Multiple responses were obtained. Options included participation as a member of a workplace or school club, as part of a club mainly comprising people from the same city or prefecture, in sports or fitness classes held at public facilities, at private membership-based sports clubs, individually, freely with community or workplace friends, at community or workplace events, with family members, or in other formats. Based on these responses, the participants were categorised into four groups according to their exercise arrangement: those who have not exercised were classified as ‘non-exercising’, those who selected only ‘individually’ and no other options were classified as ‘exercising alone’, those who selected one or more group-based options and did not select ‘individually’ were classified as ‘exercising with others’, and those who selected both ‘individually’ and any group-based options were classified as ‘a mixed type’. BMI BMI was calculated as self-reported weight (kg) divided by height squared (m²). Classification was based on the guidelines of the Japan Society for the Study of Obesity: individuals with a BMI < 18.5 kg/m 2 were defined as underweight, those with a BMI between 18.5 and < 25 kg/m 2 as normal weight, and those with a BMI ≥ 25 kg/m 2 as obese [ 23 ]. A BMI of ≥ 25 kg/m 2 is associated with more than double the risk of developing lifestyle-related diseases, such as type 2 diabetes, hypertension, and dyslipidaemia. An observational study in Japan demonstrated a U-shaped association between BMI and mortality, indicating increased mortality risks for both underweight and obese individuals [ 24 ]. Based on this evidence, both underweight and obesity were treated as indicators of physical unhealthiness in the present study. Subjective health Subjective health was assessed based on the participants’ responses to a question asking how they would describe their current health status. Response options included ‘healthy’, ‘somewhat healthy’, ‘somewhat unhealthy’, and ‘unhealthy’. In accordance with a previous study [ 17 ], the responses were dichotomised for analysis. Participants who answered ‘healthy’ or ‘somewhat healthy’ were classified as having good subjective health (coded as 1), whereas those who answered ‘somewhat unhealthy’ or ‘unhealthy’ were classified as having poor subjective health (coded as 0). Social interaction Social interaction was assessed based on the participants’ responses to a question regarding the frequency of their interactions with others in their community. Response options included ‘often’, ‘to some extent’, ‘not much’, and ‘not at all’. Responses were dichotomised for mediation analysis. Participants who answered ‘often’ or ‘to some extent’ were classified as having social interaction (coded as 1), whereas those who answered ‘not much’ or ‘not at all’ were classified as having no social interaction (coded as 0). Exercise habits Exercise habits were assessed only in participants who reported engaging in exercise. These individuals were asked whether they had engaged in light, sweat-inducing physical activity or sports for at least 30 min per session over the past year. Those who answered affirmatively were asked to report the number of days they maintained this habit annually. According to the definition provided by the Ministry of Health, Labour and Welfare, individuals who engage in physical activity for at least 30 min per session, at least twice a week, for ≥ 1 year, are classified as regular exercisers [ 3 ]. Based on this criterion, a binary variable was constructed: participants who met the threshold were coded as having an exercise habit (1), and those who did not were coded as having no exercise habit (0). Covariates The following variables were included as covariates in the statistical models: sex (men or women), age group (18–34, 35–64, or ≥ 65 years), urban scale (designated city, large city, small city, or rural area), living arrangement (living alone or with others), employment status (employed or not), educational attainment (college graduate or not), and annual household income (< 2 million, 2–5 million, 5–10 million, or ≥ 10 million yen). In addition, social interaction and exercise habits were included as covariates in models in which they were not specified as mediators. Statistical analyses Positive effect of exercising with others This study used logistic regression analysis to examine the association between exercise arrangement and health outcomes, including subjective health and BMI. The analysis was performed in two stages. First, this study estimated the associations between (1) exercise participation and health outcomes in the full sample and (2) exercise with others and health outcomes among exercise participants only. Subjective health was analysed as a binary outcome (good = 1, poor = 0), whereas BMI was separately examined for underweight (BMI < 18.5 kg/m 2 ) and obesity (BMI ≥ 25 kg/m 2 ), each treated as a binary variable. All models included covariates, such as sex, age group, urban scale, living arrangement, employment status, educational level, income, social interaction, and exercise habits. Mechanisms underlying the health outcomes of exercising with others To explore the underlying mechanisms, causal mediation analyses were performed using social interaction and exercise habits as mediators. Following the counterfactual-based framework proposed by VanderWeele and Vansteelandt [ 25 ], this study estimated the natural direct effects (NDEs) and natural indirect effects (NIEs) of exercising with others on each health outcome. Separate models were constructed for each mediator using logistic regression, adjusting for the same covariates. Interaction terms between the exposure and mediator were included to account for potential effect modifications. This mediation analysis assumed no unmeasured confounding between exposure, mediator, and outcome and cross-world independence, as required by counterfactual-based frameworks. Given the cross-sectional nature of the data, temporal ordering between exercise arrangements, mediators, and health outcomes cannot be strictly established; thus, the mediation findings should be interpreted with caution. Social interaction, although measured as general community interaction, was considered a proxy for interpersonal connectedness fostered through exercise participation, which may influence health behaviours. All statistical analyses were performed using Stata version 18. Results Characteristics Table 1 presents the characteristics of the participants across the four exercise groups: non-exercising, exercising alone, exercising with others, and a mixed type. The proportion of BMI categories significantly varied according to the exercise type (p < 0.001). The prevalence of underweight was significantly higher in the exercising alone group (11.4%) than in the exercising with others (10.1%) and mixed-type (10.0%) groups, with the lowest rate observed in the mixed-type group. The proportion of patients with normal BMI was highest in the mixed-type group (68.4%). Subjective health status also significantly differed among the groups (p < 0.001). Compared with the exercising with others group, the exercising alone group reported significantly lower rates of good subjective health (85.2%); the exercising with others (89.7%) and mixed-type groups (89.5%) exhibited significantly higher rates. Table 1 Characteristics of individuals according to exercise arrangement Variable Non-exercising Exercising alone Exercising with others Mixed type p value BMI a (%) Underweight 13.9 11.4 10.1 10.0 < 0.001 Normal 60.2 66.4 68.0 68.4 Obesity 25.9 22.2 22.0 21.6 Subjective health (%) Good 76.8 85.2 89.7 89.5 < 0.001 Sex (%) Men 45.1 56.2 51.6 53.0 < 0.001 Age (%) 18–34 16.1 20.1 25.7 21.7 < 0.001 35–64 63.3 56.9 51.9 47.9 ≥ 65 20.6 23.0 22.4 30.4 Social interaction (%) Yes 25.7 29.1 45.9 44.3 < 0.001 Exercise habit (%) Yes - 31.8 36.5 40.5 < 0.001 Number of observations 5,281 10,833 5,692 6,874 P-values were calculated using the chi-squared test. a BMI, body mass index Association between exercising with others and health outcomes Table 2 presents the adjusted associations of exercise participation and arrangement with underweight, obesity, and subjective health. Panel A shows that exercise participation was significantly associated with a lower likelihood of being underweight (odds ratio [OR] = 0.797; 95% confidence interval [CI], 0.723–0.879) and obese (OR = 0.816; 95% CI, 0.756–0.880) and a higher likelihood of reporting good subjective health (OR = 1.563; 95% CI, 1.441–1.694; all p < 0.001). Table 2 Logistic regressions of health outcomes Outcome Underweight Obesity Subjective health Panel A. Full sample (N = 28,680) Exercise participation 0.797*** (0.723–0.879) 0.816*** (0.756–0.880) 1.563*** (1.441–1.694) Panel B. Exercisers only (N = 23,399); ref.=Exercising alone Exercising with others 0.818*** (0.733–0.912) 1.079* (0.995–1.171) 1.337*** (1.206–1.482) Mixed type 0.848*** (0.765–0.940) 1.029 (0.952–1.111) 1.309*** (1.189–1.441) Odds ratios are reported with 95% confidence intervals in parentheses. The models were adjusted for sex, age, urban scale, living arrangement, employment status, educational attainment, annual household income, social interaction, and exercise habits. *** p < 0.01, ** p < 0.05, * p < 0.1. When focusing on exercise type (Panel B), those who exercised with others showed significantly lower odds of being underweight (OR = 0.818; 95% CI, 0.733–0.912) and higher odds of having good subjective health (OR = 1.337; 95% CI, 1.206–1.482) compared with those who exercised alone. The mixed-type group also exhibited significantly lower odds of being underweight (OR = 0.848; 95% CI, 0.765–0.940) and higher odds of having good subjective health (OR = 1.309; 95% CI, 1.189–1.441). For obesity, a marginally significant positive association was observed in the exercising with others group (OR = 1.079; 95% CI, 0.995–1.171), whereas the mixed-type group showed no significant difference compared with the exercising alone group. Mediation analysis of social interaction and exercise habits Table 3 and Table 4 presents the mediating effects of social interactions and exercise habits on the association between exercise type and health outcomes. Table 3 Mediation analysis for health outcomes (Mediator = social interaction) Underweight Obesity Subjective health NIE a Exercising alone vs. exercising with others 0.994 (0.969–1.020) 1.008 (0.988–1.027) 1.056*** (1.029–1.084) Exercising alone vs. mixed type 0.997 (0.979–1.016) 0.999 (0.985–1.013) 1.042*** (1.023–1.061) NDE b Exercising alone vs. exercising with others 0.823*** (0.741–0.915) 1.075** (0.994–1.162) 1.321*** (1.191–1.464) Exercising alone vs. mixed type 0.851*** (0.771–0.939) 1.035 (0.962–1.115) 1.297*** (1.179–1.427) N 23,399 23,399 23,399 Odds ratios are reported with 95% confidence intervals in parentheses. The models were adjusted for sex, age, urban scale, living arrangement, employment status, educational attainment, annual household income, and exercise habits. *** p < 0.01, ** p < 0.05, * p < 0.1. a NIE, natural indirect effect; b NDE, natural direct effect. Table 4 Mediation analysis for health outcomes (Mediator = exercise habits) Underweight Obesity Subjective health NIE a Exercising alone vs. exercising with others 0.998 (0.990–1.006) 0.994* (0.988–1.001) 1.034*** (1.021–1.048) Exercising alone vs. mixed type 1.001 (0.991–1.012) 0.979*** (0.971–0.988) 1.048*** (1.034–1.063) NDE b Exercising alone vs. exercising with others 0.830*** (0.748–0.920) 1.074** (0.995–1.159) 1.294*** (1.197–1.465) Exercising alone vs. mixed type 0.855*** (0.775–0.943) 1.040 (0.967–1.119) 1.294*** (1.178–1.422) N 23,399 23,399 23,399 Odds ratios are reported with 95% confidence intervals in parentheses. The models were adjusted for sex, age, urban scale, living arrangement, employment status, educational attainment, annual household income, and social interaction. *** p < 0.01, ** p < 0.05, * p < 0.1. a NIE, natural indirect effect; b NDE, natural direct effect. When social interaction was used as a mediator, significant indirect effects (NIE) were observed only for subjective health. Compared with exercising alone, exercising with others (OR = 1.056; 95% CI, 1.029–1.084) and mixed-type exercise (OR = 1.042; 95% CI, 1.023–1.061) were associated with higher odds of reporting good subjective health through increased social interaction. No significant indirect effects were observed for being underweight or obese. The NDE remained significant, and exercising with others (OR = 0.823; 95% CI, 0.741–0.915) and mixed-type exercise (OR = 0.851; 95% CI, 0.771–0.939) were associated with lower odds of being underweight, and both arrangements were associated with higher odds of having good subjective health (ORs > 1.29, all p < 0.001). Similar patterns were observed with exercise habits as mediators. Significant indirect effects were found for subjective health (exercising with others: OR = 1.034, 95% CI: 1.021–1.048; mixed-type exercise: OR = 1.048, 95% CI: 1.034–1.063) and obesity in the mixed-type group (OR = 0.979; 95% CI, 0.971–0.988). Direct effects also remained significant, particularly for underweight and subjective health, indicating that both mediators partially explained the association between exercise type and health outcomes but did not fully account for it. Discussion This study aimed to clarify the association between exercising with others and health outcomes among Japanese adults by focusing on both subjective and objective indicators. The findings demonstrate the following three key points. First, exercise participation was significantly associated with better health outcomes, including a lower likelihood of being underweight or obese and higher likelihood of reporting good subjective health. Second, among the exercise participants, those who exercised with others or engaged in mixed-type exercise (both individually and with others) reported significantly lower odds of being underweight and higher odds of having good subjective health than those who exercised alone. However, no significant association was observed with obesity, except for a marginal trend among those who exercised with others. Third, mediation analyses revealed that social interaction and exercise habits partially explained the association between exercising with others and subjective health; however, their mediating roles in BMI outcomes were negligible. The negative association between exercising with others and being underweight aligns with findings of previous studies, suggesting that group-based physical activity contributes to better nutritional and metabolic statuses [ 26 , 27 ], possibly through reduced psychological stress and improved appetite regulation. Socially active exercisers may also be more likely to engage in muscle-strengthening or resistance-based activities [ 28 ], which help maintain muscle mass and prevent excessive weight loss. This is particularly relevant in Japan, where the prevalence of underweight, particularly among women, is a notable public health concern. The limited association between exercising with others and obesity reduction may, in part, be explained by the post-exercise social eating behaviours commonly associated with group-based exercise. In Japan, group exercise often serves as a social activity, and it is not uncommon for participants to gather for meals or drinks afterwards, which may offset the potential caloric expenditure achieved during exercise [ 29 ]. Previous research on the social facilitation of eating has consistently demonstrated that individuals tend to consume 30–50% more food when eating in the presence of others than when eating alone [ 30 , 31 ]. The strong positive association between group-based exercise and subjective health supports theoretical frameworks, such as SDT, which emphasises the importance of fulfilling basic psychological needs, particularly relatedness. Exercising with others may provide emotional support, a sense of belonging, and mutual encouragement, all of which contribute to enhanced intrinsic motivation and well-being [ 20 ]. The observed indirect effects of social interaction confirm that psychological and social factors are important pathways for improved subjective health, although their effect sizes were modest. Exercise habits also partially mediated these associations, suggesting that social settings encourage greater consistency and adherence to physical activity through social norms and accountability. However, the persistence of significant direct effects implies that additional mechanisms, such as enjoyment, increased self-efficacy, or perceived competence, may also contribute to health benefits. Future studies should incorporate these psychological constructs to further elucidate the mechanisms underlying the benefits of group-based exercises. This study has several notable strengths. First, it utilised a large nationally representative sample of Japanese adults, thereby enhancing the generalisability of the findings to a broader population. Second, both subjective (self-rated health) and objective (BMI) health indicators were simultaneously examined to provide a more comprehensive understanding of the health benefits of exercising with others. Third, by applying a counterfactual-based mediation framework, this study advances previous research by empirically testing the psychological and behavioural mechanisms underlying the association between group-based exercise and health outcomes. However, this study has some limitations. Most importantly, the cross-sectional design precludes causal inference, and reverse causality cannot be ruled out; for instance, individuals with better health may be more inclined to participate in group-based exercise. Additionally, all variables, including BMI, exercise habits, and social interaction, were self-reported, which may have introduced recall and social desirability biases. The measure of social interaction was limited to general community interactions and may not have fully captured the quality or intensity of exercise-specific social associations. Furthermore, potential confounding factors, such as dietary patterns, personality traits (e.g. extraversion), and preexisting health conditions, were not assessed. These limitations should be addressed in future studies using longitudinal designs, objective measures of physical activity and health outcomes, and more refined assessments of social interaction. Conclusion Exercising with others contributes to improved subjective health, with particularly notable indirect effects through social interaction. In particular, its effectiveness in preventing underweight is important in Japan, as it provides insights for addressing public health challenges. Future health promotion policies can enhance not only the physical effects of exercise but also the initiatives that promote social interaction. Declarations Informed consent: No new informed consent was required for this secondary analysis of de-identified public-use data. The original survey was conducted by the Japan Sports Agency, and the publicly released dataset contains no directly identifying information. Ethical approval: All analyses were conducted in accordance with institutional and national guidelines and with the principles of the 1964 Declaration of Helsinki and its later amendments, where applicable to anonymized secondary data. The primary survey was conducted by the Japan Sports Agency. Author Contribution S.S. wrote the main manuscript text and M.M. revised. All authors reviewed the manuscript. 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Sasaki","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA70lEQVRIiWNgGAWjYLCCBAZmBjb2xuYHH4AcNnZitfDzHD5mOAOkhZk4e5gZJGekJUjzQNj4gXx7A/OHBwzWcgZnzhgY2/zaJs/HzMD44WMObi0GZw6wSSQwpBsbHO8xeJzbd9uwjZmBWXLmNjxaJBLYgH45nLgBZEtuz21GoBY2Zl48WuRnJDB/AGu5kWMgbdlz256gFoYbCQwSIC0zQd5n+HE7kaAWgzMH2yQSDNKNwYHc23A7uY2ZsRmvX+Tbmw9//FFhLQeOyh9/btvOb28++OEjPocxMDYA7YKx22AixIM/pCgeBaNgFIyCkQIAfCFQBSy5nwIAAAAASUVORK5CYII=","orcid":"","institution":"University of Tsukuba","correspondingAuthor":true,"prefix":"","firstName":"Soshi","middleName":"","lastName":"Sasaki","suffix":""},{"id":546133827,"identity":"53cad771-3cc1-4b3f-b124-aab5a24873db","order_by":1,"name":"Midori Matsushima","email":"","orcid":"","institution":"University of Tsukuba","correspondingAuthor":false,"prefix":"","firstName":"Midori","middleName":"","lastName":"Matsushima","suffix":""}],"badges":[],"createdAt":"2025-10-31 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16:03:24","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":754516,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-8000528/v1/ad8312f3-f1dc-4a0a-b48d-c9b62ff242cb.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Benefits of exercising with others on physical and mental health in Japan: understanding the underlying mechanisms","fulltext":[{"header":"Introduction","content":"\u003cp\u003e\u003cb\u003eTitle\u003c/b\u003e: Benefits of exercising with others on physical and mental health in Japan: understanding the underlying mechanisms\u003c/p\u003e\u003cp\u003eLow physical activity poses various health challenges, including increased risk of lifestyle-related diseases and weakened immune function [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. In Japan, only 33.5% of men and 31.5% of women engage in regular exercise. Among working-age individuals in their 20s\u0026ndash;40s, these numbers decrease further to 21.1% for men and 20.4% for women [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], falling short of the national targets (36.0% for men, 33.0% for women) [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Conditions associated with physical inactivity account for approximately one-third of medical expenses among those aged\u0026thinsp;\u0026ge;\u0026thinsp;65 years in Japan [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], and the economic burden extends beyond medical costs to include productivity losses owing to health-related absenteeism [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Additionally, individuals who are physically inactive during their youth are more likely to experience a decline in work capacity as adults [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], emphasising the importance of early preventive interventions.\u003c/p\u003e\u003cp\u003eIn parallel, another unique public health concern in Japan is the high prevalence of underweight among young women. Approximately 20% of women in their 20s are underweight, a figure comparable to that observed in low- and middle-income countries and higher than that in other developed nations [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Although obesity is widely recognised as a risk factor for chronic diseases, being underweight also carries significant health risks, including nutritional deficiencies and osteoporosis [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Addressing underweight among young women in Japan requires a dual approach: improving both dietary intake and physical activity [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Regular exercise may play a key role not only in preventing excessive weight loss but also in promoting overall metabolic health, suggesting that physical activity promotion can contribute to resolving underweight-related health risks [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e, \u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eIn efforts to promote health benefits, growing attention has been paid to the role of social interaction in exercise settings. Although the underlying mechanisms through which physical activity promotes health remain a subject of ongoing research, an emerging hypothesis suggests that exercising with others yields greater health benefits than exercising alone [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e, \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Social interaction during physical activity may contribute to psychological well-being by facilitating communication, mutual encouragement, and shared experiences [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eMoreover, participation in group-based exercise is associated with the formation of supportive social networks, which may help sustain long-term health behaviours [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. The benefits of social interaction through exercise are not limited to mental health; strengthened social connectedness, social support, and peer bonding are associated with favourable physical health outcomes, including reduced mortality rates and decreased risk of chronic diseases [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. In addition to these social and behavioural explanations, some researchers have drawn on psychological theories to better understand the mechanisms underlying these effects. One such framework is the self-determination theory (SDT), which identifies three basic psychological needs\u0026mdash;autonomy, competence, and relatedness\u0026mdash;as essential for promoting motivation and well-being [\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. Group-based exercise may contribute to fulfilling these needs, especially relatedness, thereby enhancing intrinsic motivation and increasing adherence to physical activity.\u003c/p\u003e\u003cp\u003eSeveral studies have empirically demonstrated the health benefits of exercising with others. For example, large-scale Japanese studies focusing on older adults have shown that social exercise is associated with better subjective health and greater physical activity levels, even after accounting for exercise frequency [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e, \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e]. However, such evidence is largely limited to the older population, and research involving younger generations in Japan remains lacking, despite growing concerns about physical inactivity among this demographic. Furthermore, most existing studies have primarily examined mental health outcomes, with limited investigations into how social exercise may affect physical health through psychosocial mechanisms. Addressing these research gaps is essential to designing effective and inclusive interventions for different age groups.\u003c/p\u003e\u003cp\u003eBuilding on previous findings, two theoretical pathways have been proposed to explain how exercising with others contributes to improved health outcomes. The first highlights the role of social networks and interpersonal connections developed through group-based physical activities. Such interactions can foster emotional support, a sense of belonging, and enhanced motivation to continue exercising [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. The second pathway emphasises behavioural engagement: exercising with others may increase accountability and consistency in physical activity owing to mutual expectations and social norms [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eDrawing on these mechanisms, the present study aimed to clarify how exercising with others contributes to better health outcomes among Japanese adults. Specifically, this study examined the following two research questions: (1) Do Japanese adults who exercise with others report better health outcomes than those who exercise alone? and (2) To what extent are these associations mediated by increased social interaction and higher exercise volume? To address these questions, this study examined body mass index (BMI) and subjective health as health indicators and performed mediation analysis to clarify the psychological and behavioural mechanisms linking social exercise to health. This study contributes to the literature by examining both subjective and objective health outcomes in relation to social exercise and by employing mediation analysis to clarify the psychological and behavioural pathways through which exercising with others may exert health-promoting effects. In doing so, it offers valuable insights into the development of evidence-based interventions and health promotion policies targeting diverse age groups and addressing Japan\u0026rsquo;s unique public health challenges.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eMaterials\u003c/h2\u003e\u003cp\u003eThis study used cross-sectional data from a nationwide survey on public awareness of sports participation in Japan conducted by the Japan Sports Agency from 7 to 27 December 2022 [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. A total of 40,000 individuals aged 18\u0026ndash;79 years were selected through stratified and random sampling strategies based on age, sex, and region to ensure representativeness of the Japanese adult population.\u003c/p\u003e\u003cp\u003eIn the study, 11,320 respondents were excluded based on the following criteria: (1) having a disability certificate, being bedridden, being unable to exercise in the past year, or being advised by a physician to refrain from physical activity (n\u0026thinsp;=\u0026thinsp;1,973) and (2) selecting \u0026lsquo;Do not want to answer\u0026rsquo; or \u0026lsquo;Not sure\u0026rsquo; for any key demographic or health-related questions (n\u0026thinsp;=\u0026thinsp;9,347).\u003c/p\u003e\u003cp\u003eThe final analytical sample comprised 28,680 individuals (15,045 men [52.5%] and 13,635 women [47.5%]), with a mean age of 50.2 years (standard deviation\u0026thinsp;=\u0026thinsp;16.3).\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eMeasurements\u003c/h3\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003eExercise arrangement\u003c/h2\u003e\u003cp\u003eThe participants were first asked whether they had engaged in any of the 60 listed types of exercise or sports over the past year. Individuals were classified as exercise participants if they selected at least one of the 58 activity options, excluding \u0026lsquo;have not exercised or played sports in the past year\u0026rsquo; and \u0026lsquo;not sure\u0026rsquo;. They were instructed to exclude exercises performed as part of school education or employment but to include home-based activities (e.g. via online platforms or television).\u003c/p\u003e\u003cp\u003eParticipants who reported exercising were then asked how they usually engaged in these activities. Multiple responses were obtained. Options included participation as a member of a workplace or school club, as part of a club mainly comprising people from the same city or prefecture, in sports or fitness classes held at public facilities, at private membership-based sports clubs, individually, freely with community or workplace friends, at community or workplace events, with family members, or in other formats.\u003c/p\u003e\u003cp\u003eBased on these responses, the participants were categorised into four groups according to their exercise arrangement: those who have not exercised were classified as \u0026lsquo;non-exercising\u0026rsquo;, those who selected only \u0026lsquo;individually\u0026rsquo; and no other options were classified as \u0026lsquo;exercising alone\u0026rsquo;, those who selected one or more group-based options and did not select \u0026lsquo;individually\u0026rsquo; were classified as \u0026lsquo;exercising with others\u0026rsquo;, and those who selected both \u0026lsquo;individually\u0026rsquo; and any group-based options were classified as \u0026lsquo;a mixed type\u0026rsquo;.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eBMI\u003c/h3\u003e\n\u003cp\u003eBMI was calculated as self-reported weight (kg) divided by height squared (m\u0026sup2;). Classification was based on the guidelines of the Japan Society for the Study of Obesity: individuals with a BMI\u0026thinsp;\u0026lt;\u0026thinsp;18.5 kg/m\u003csup\u003e2\u003c/sup\u003e were defined as underweight, those with a BMI between 18.5 and \u0026lt;\u0026thinsp;25 kg/m\u003csup\u003e2\u003c/sup\u003e as normal weight, and those with a BMI\u0026thinsp;\u0026ge;\u0026thinsp;25 kg/m\u003csup\u003e2\u003c/sup\u003e as obese [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eA BMI of \u0026ge;\u0026thinsp;25 kg/m\u003csup\u003e2\u003c/sup\u003e is associated with more than double the risk of developing lifestyle-related diseases, such as type 2 diabetes, hypertension, and dyslipidaemia. An observational study in Japan demonstrated a U-shaped association between BMI and mortality, indicating increased mortality risks for both underweight and obese individuals [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. Based on this evidence, both underweight and obesity were treated as indicators of physical unhealthiness in the present study.\u003c/p\u003e\n\u003ch3\u003eSubjective health\u003c/h3\u003e\n\u003cp\u003eSubjective health was assessed based on the participants\u0026rsquo; responses to a question asking how they would describe their current health status. Response options included \u0026lsquo;healthy\u0026rsquo;, \u0026lsquo;somewhat healthy\u0026rsquo;, \u0026lsquo;somewhat unhealthy\u0026rsquo;, and \u0026lsquo;unhealthy\u0026rsquo;.\u003c/p\u003e\u003cp\u003eIn accordance with a previous study [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e], the responses were dichotomised for analysis. Participants who answered \u0026lsquo;healthy\u0026rsquo; or \u0026lsquo;somewhat healthy\u0026rsquo; were classified as having good subjective health (coded as 1), whereas those who answered \u0026lsquo;somewhat unhealthy\u0026rsquo; or \u0026lsquo;unhealthy\u0026rsquo; were classified as having poor subjective health (coded as 0).\u003c/p\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003eSocial interaction\u003c/h2\u003e\u003cp\u003e Social interaction was assessed based on the participants\u0026rsquo; responses to a question regarding the frequency of their interactions with others in their community. Response options included \u0026lsquo;often\u0026rsquo;, \u0026lsquo;to some extent\u0026rsquo;, \u0026lsquo;not much\u0026rsquo;, and \u0026lsquo;not at all\u0026rsquo;.\u003c/p\u003e\u003cp\u003eResponses were dichotomised for mediation analysis. Participants who answered \u0026lsquo;often\u0026rsquo; or \u0026lsquo;to some extent\u0026rsquo; were classified as having social interaction (coded as 1), whereas those who answered \u0026lsquo;not much\u0026rsquo; or \u0026lsquo;not at all\u0026rsquo; were classified as having no social interaction (coded as 0).\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eExercise habits\u003c/h3\u003e\n\u003cp\u003eExercise habits were assessed only in participants who reported engaging in exercise. These individuals were asked whether they had engaged in light, sweat-inducing physical activity or sports for at least 30 min per session over the past year. Those who answered affirmatively were asked to report the number of days they maintained this habit annually.\u003c/p\u003e\u003cp\u003eAccording to the definition provided by the Ministry of Health, Labour and Welfare, individuals who engage in physical activity for at least 30 min per session, at least twice a week, for \u0026ge;\u0026thinsp;1 year, are classified as regular exercisers [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Based on this criterion, a binary variable was constructed: participants who met the threshold were coded as having an exercise habit (1), and those who did not were coded as having no exercise habit (0).\u003c/p\u003e\n\u003ch3\u003eCovariates\u003c/h3\u003e\n\u003cp\u003eThe following variables were included as covariates in the statistical models: sex (men or women), age group (18\u0026ndash;34, 35\u0026ndash;64, or \u0026ge;\u0026thinsp;65 years), urban scale (designated city, large city, small city, or rural area), living arrangement (living alone or with others), employment status (employed or not), educational attainment (college graduate or not), and annual household income (\u0026lt;\u0026thinsp;2\u0026nbsp;million, 2\u0026ndash;5\u0026nbsp;million, 5\u0026ndash;10\u0026nbsp;million, or \u0026ge;\u0026thinsp;10\u0026nbsp;million yen). In addition, social interaction and exercise habits were included as covariates in models in which they were not specified as mediators.\u003c/p\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003eStatistical analyses\u003c/h2\u003e\u003cdiv id=\"Sec12\" class=\"Section3\"\u003e\u003ch2\u003ePositive effect of exercising with others\u003c/h2\u003e\u003cp\u003eThis study used logistic regression analysis to examine the association between exercise arrangement and health outcomes, including subjective health and BMI. The analysis was performed in two stages.\u003c/p\u003e\u003cp\u003eFirst, this study estimated the associations between (1) exercise participation and health outcomes in the full sample and (2) exercise with others and health outcomes among exercise participants only. Subjective health was analysed as a binary outcome (good\u0026thinsp;=\u0026thinsp;1, poor\u0026thinsp;=\u0026thinsp;0), whereas BMI was separately examined for underweight (BMI\u0026thinsp;\u0026lt;\u0026thinsp;18.5 kg/m\u003csup\u003e2\u003c/sup\u003e) and obesity (BMI\u0026thinsp;\u0026ge;\u0026thinsp;25 kg/m\u003csup\u003e2\u003c/sup\u003e), each treated as a binary variable. All models included covariates, such as sex, age group, urban scale, living arrangement, employment status, educational level, income, social interaction, and exercise habits.\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003eMechanisms underlying the health outcomes of exercising with others\u003c/h2\u003e\u003cp\u003eTo explore the underlying mechanisms, causal mediation analyses were performed using social interaction and exercise habits as mediators. Following the counterfactual-based framework proposed by VanderWeele and Vansteelandt [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e], this study estimated the natural direct effects (NDEs) and natural indirect effects (NIEs) of exercising with others on each health outcome. Separate models were constructed for each mediator using logistic regression, adjusting for the same covariates. Interaction terms between the exposure and mediator were included to account for potential effect modifications.\u003c/p\u003e\u003cp\u003eThis mediation analysis assumed no unmeasured confounding between exposure, mediator, and outcome and cross-world independence, as required by counterfactual-based frameworks. Given the cross-sectional nature of the data, temporal ordering between exercise arrangements, mediators, and health outcomes cannot be strictly established; thus, the mediation findings should be interpreted with caution. Social interaction, although measured as general community interaction, was considered a proxy for interpersonal connectedness fostered through exercise participation, which may influence health behaviours.\u003c/p\u003e\u003cp\u003eAll statistical analyses were performed using Stata version 18.\u003c/p\u003e\u003c/div\u003e"},{"header":"Results","content":"\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\u003ch2\u003eCharacteristics\u003c/h2\u003e\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e presents the characteristics of the participants across the four exercise groups: non-exercising, exercising alone, exercising with others, and a mixed type. The proportion of BMI categories significantly varied according to the exercise type (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). The prevalence of underweight was significantly higher in the exercising alone group (11.4%) than in the exercising with others (10.1%) and mixed-type (10.0%) groups, with the lowest rate observed in the mixed-type group. The proportion of patients with normal BMI was highest in the mixed-type group (68.4%). Subjective health status also significantly differed among the groups (p\u0026thinsp;\u0026lt;\u0026thinsp;0.001). Compared with the exercising with others group, the exercising alone group reported significantly lower rates of good subjective health (85.2%); the exercising with others (89.7%) and mixed-type groups (89.5%) exhibited significantly higher rates.\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\u003eCharacteristics of individuals according to exercise arrangement\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"7\"\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=\"char\" char=\".\" class=\"colspec\" colname=\"c7\" colnum=\"7\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eVariable\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eNon-exercising\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eExercising alone\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eExercising\u003c/p\u003e\u003cp\u003ewith others\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eMixed type\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c7\"\u003e\u003cp\u003ep value\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eBMI\u003csup\u003ea\u003c/sup\u003e (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUnderweight\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e13.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e11.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e10.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e10.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNormal\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e60.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e66.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e68.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e68.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eObesity\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e25.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e22.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e22.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e21.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSubjective health (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eGood\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e76.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e85.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e89.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e89.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSex (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMen\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e45.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e56.2\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e51.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e53.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eAge (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e18\u0026ndash;34\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e16.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e20.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e25.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e21.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e35\u0026ndash;64\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e63.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e56.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e51.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e47.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e\u0026ge;\u0026thinsp;65\u003c/p\u003e \u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e20.6\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e23.0\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e22.4\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e30.4\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eSocial interaction (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e25.7\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e29.1\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e45.9\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e44.3\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercise habit (%)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eYes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e31.8\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e36.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e40.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c7\"\u003e\u003cp\u003e\u0026lt;\u0026thinsp;0.001\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNumber of observations\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e5,281\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e10,833\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e5,692\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c6\"\u003e\u003cp\u003e6,874\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c7\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"7\"\u003eP-values were calculated using the chi-squared test.\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"7\"\u003e\u003csup\u003ea\u003c/sup\u003eBMI, body mass index\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\u003ch2\u003eAssociation between exercising with others and health outcomes\u003c/h2\u003e\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e presents the adjusted associations of exercise participation and arrangement with underweight, obesity, and subjective health. Panel A shows that exercise participation was significantly associated with a lower likelihood of being underweight (odds ratio [OR]\u0026thinsp;=\u0026thinsp;0.797; 95% confidence interval [CI], 0.723\u0026ndash;0.879) and obese (OR\u0026thinsp;=\u0026thinsp;0.816; 95% CI, 0.756\u0026ndash;0.880) and a higher likelihood of reporting good subjective health (OR\u0026thinsp;=\u0026thinsp;1.563; 95% CI, 1.441\u0026ndash;1.694; all p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\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\u003eLogistic regressions of health outcomes\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eOutcome\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUnderweight\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eObesity\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSubjective health\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePanel A. Full sample (N\u0026thinsp;=\u0026thinsp;28,680)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercise participation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.797*** (0.723\u0026ndash;0.879)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.816*** (0.756\u0026ndash;0.880)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e1.563*** (1.441\u0026ndash;1.694)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003ePanel B. Exercisers only (N\u0026thinsp;=\u0026thinsp;23,399); ref.=Exercising alone\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercising with others\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.818*** (0.733\u0026ndash;0.912)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1.079* (0.995\u0026ndash;1.171)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e1.337*** (1.206\u0026ndash;1.482)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eMixed type\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.848*** (0.765\u0026ndash;0.940)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1.029 (0.952\u0026ndash;1.111)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e1.309*** (1.189\u0026ndash;1.441)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003eOdds ratios are reported with 95% confidence intervals in parentheses. The models were adjusted for sex, age, urban scale, living arrangement, employment status, educational attainment, annual household income, social interaction, and exercise habits. \u003csup\u003e***\u003c/sup\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.01, \u003csup\u003e**\u003c/sup\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e*\u003c/sup\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.1.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eWhen focusing on exercise type (Panel B), those who exercised with others showed significantly lower odds of being underweight (OR\u0026thinsp;=\u0026thinsp;0.818; 95% CI, 0.733\u0026ndash;0.912) and higher odds of having good subjective health (OR\u0026thinsp;=\u0026thinsp;1.337; 95% CI, 1.206\u0026ndash;1.482) compared with those who exercised alone. The mixed-type group also exhibited significantly lower odds of being underweight (OR\u0026thinsp;=\u0026thinsp;0.848; 95% CI, 0.765\u0026ndash;0.940) and higher odds of having good subjective health (OR\u0026thinsp;=\u0026thinsp;1.309; 95% CI, 1.189\u0026ndash;1.441).\u003c/p\u003e\u003cp\u003eFor obesity, a marginally significant positive association was observed in the exercising with others group (OR\u0026thinsp;=\u0026thinsp;1.079; 95% CI, 0.995\u0026ndash;1.171), whereas the mixed-type group showed no significant difference compared with the exercising alone group.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\u003ch2\u003eMediation analysis of social interaction and exercise habits\u003c/h2\u003e\u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e presents the mediating effects of social interactions and exercise habits on the association between exercise type and health outcomes.\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\u003eMediation analysis for health outcomes (Mediator\u0026thinsp;=\u0026thinsp;social interaction)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUnderweight\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eObesity\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSubjective health\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNIE\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercising alone vs. exercising with others\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.994 (0.969\u0026ndash;1.020)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.008 (0.988\u0026ndash;1.027)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.056*** (1.029\u0026ndash;1.084)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercising alone vs. mixed type\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.997 (0.979\u0026ndash;1.016)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.999 (0.985\u0026ndash;1.013)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.042*** (1.023\u0026ndash;1.061)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNDE\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercising alone vs. exercising with others\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.823*** (0.741\u0026ndash;0.915)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.075** (0.994\u0026ndash;1.162)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.321*** (1.191\u0026ndash;1.464)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercising alone vs. mixed type\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.851*** (0.771\u0026ndash;0.939)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.035 (0.962\u0026ndash;1.115)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.297*** (1.179\u0026ndash;1.427)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e23,399\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e23,399\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e23,399\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003eOdds ratios are reported with 95% confidence intervals in parentheses. The models were adjusted for sex, age, urban scale, living arrangement, employment status, educational attainment, annual household income, and exercise habits. \u003csup\u003e***\u003c/sup\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.01, \u003csup\u003e**\u003c/sup\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e*\u003c/sup\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.1.\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003e\u003csup\u003ea\u003c/sup\u003eNIE, natural indirect effect; \u003csup\u003eb\u003c/sup\u003eNDE, natural direct effect.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eMediation analysis for health outcomes (Mediator\u0026thinsp;=\u0026thinsp;exercise habits)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\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\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUnderweight\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eObesity\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSubjective health\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNIE\u003csup\u003ea\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercising alone vs. exercising with others\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.998 (0.990\u0026ndash;1.006)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.994* (0.988\u0026ndash;1.001)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.034*** (1.021\u0026ndash;1.048)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercising alone vs. mixed type\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e1.001 (0.991\u0026ndash;1.012)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e0.979*** (0.971\u0026ndash;0.988)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.048*** (1.034\u0026ndash;1.063)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eNDE\u003csup\u003eb\u003c/sup\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercising alone vs. exercising with others\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.830*** (0.748\u0026ndash;0.920)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.074** (0.995\u0026ndash;1.159)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.294*** (1.197\u0026ndash;1.465)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExercising alone vs. mixed type\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e0.855*** (0.775\u0026ndash;0.943)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e1.040 (0.967\u0026ndash;1.119)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e1.294*** (1.178\u0026ndash;1.422)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eN\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003e23,399\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e23,399\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003e23,399\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003eOdds ratios are reported with 95% confidence intervals in parentheses. The models were adjusted for sex, age, urban scale, living arrangement, employment status, educational attainment, annual household income, and social interaction. \u003csup\u003e***\u003c/sup\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.01, \u003csup\u003e**\u003c/sup\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.05, \u003csup\u003e*\u003c/sup\u003ep\u0026thinsp;\u0026lt;\u0026thinsp;0.1.\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003e\u003csup\u003ea\u003c/sup\u003eNIE, natural indirect effect; \u003csup\u003eb\u003c/sup\u003eNDE, natural direct effect.\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eWhen social interaction was used as a mediator, significant indirect effects (NIE) were observed only for subjective health. Compared with exercising alone, exercising with others (OR\u0026thinsp;=\u0026thinsp;1.056; 95% CI, 1.029\u0026ndash;1.084) and mixed-type exercise (OR\u0026thinsp;=\u0026thinsp;1.042; 95% CI, 1.023\u0026ndash;1.061) were associated with higher odds of reporting good subjective health through increased social interaction. No significant indirect effects were observed for being underweight or obese. The NDE remained significant, and exercising with others (OR\u0026thinsp;=\u0026thinsp;0.823; 95% CI, 0.741\u0026ndash;0.915) and mixed-type exercise (OR\u0026thinsp;=\u0026thinsp;0.851; 95% CI, 0.771\u0026ndash;0.939) were associated with lower odds of being underweight, and both arrangements were associated with higher odds of having good subjective health (ORs\u0026thinsp;\u0026gt;\u0026thinsp;1.29, all p\u0026thinsp;\u0026lt;\u0026thinsp;0.001).\u003c/p\u003e\u003cp\u003eSimilar patterns were observed with exercise habits as mediators. Significant indirect effects were found for subjective health (exercising with others: OR\u0026thinsp;=\u0026thinsp;1.034, 95% CI: 1.021\u0026ndash;1.048; mixed-type exercise: OR\u0026thinsp;=\u0026thinsp;1.048, 95% CI: 1.034\u0026ndash;1.063) and obesity in the mixed-type group (OR\u0026thinsp;=\u0026thinsp;0.979; 95% CI, 0.971\u0026ndash;0.988). Direct effects also remained significant, particularly for underweight and subjective health, indicating that both mediators partially explained the association between exercise type and health outcomes but did not fully account for it.\u003c/p\u003e\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study aimed to clarify the association between exercising with others and health outcomes among Japanese adults by focusing on both subjective and objective indicators. The findings demonstrate the following three key points. First, exercise participation was significantly associated with better health outcomes, including a lower likelihood of being underweight or obese and higher likelihood of reporting good subjective health. Second, among the exercise participants, those who exercised with others or engaged in mixed-type exercise (both individually and with others) reported significantly lower odds of being underweight and higher odds of having good subjective health than those who exercised alone. However, no significant association was observed with obesity, except for a marginal trend among those who exercised with others. Third, mediation analyses revealed that social interaction and exercise habits partially explained the association between exercising with others and subjective health; however, their mediating roles in BMI outcomes were negligible.\u003c/p\u003e\u003cp\u003eThe negative association between exercising with others and being underweight aligns with findings of previous studies, suggesting that group-based physical activity contributes to better nutritional and metabolic statuses [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e, \u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], possibly through reduced psychological stress and improved appetite regulation. Socially active exercisers may also be more likely to engage in muscle-strengthening or resistance-based activities [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e], which help maintain muscle mass and prevent excessive weight loss. This is particularly relevant in Japan, where the prevalence of underweight, particularly among women, is a notable public health concern.\u003c/p\u003e\u003cp\u003eThe limited association between exercising with others and obesity reduction may, in part, be explained by the post-exercise social eating behaviours commonly associated with group-based exercise. In Japan, group exercise often serves as a social activity, and it is not uncommon for participants to gather for meals or drinks afterwards, which may offset the potential caloric expenditure achieved during exercise [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. Previous research on the social facilitation of eating has consistently demonstrated that individuals tend to consume 30\u0026ndash;50% more food when eating in the presence of others than when eating alone [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e].\u003c/p\u003e\u003cp\u003eThe strong positive association between group-based exercise and subjective health supports theoretical frameworks, such as SDT, which emphasises the importance of fulfilling basic psychological needs, particularly relatedness. Exercising with others may provide emotional support, a sense of belonging, and mutual encouragement, all of which contribute to enhanced intrinsic motivation and well-being [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. The observed indirect effects of social interaction confirm that psychological and social factors are important pathways for improved subjective health, although their effect sizes were modest.\u003c/p\u003e\u003cp\u003eExercise habits also partially mediated these associations, suggesting that social settings encourage greater consistency and adherence to physical activity through social norms and accountability. However, the persistence of significant direct effects implies that additional mechanisms, such as enjoyment, increased self-efficacy, or perceived competence, may also contribute to health benefits. Future studies should incorporate these psychological constructs to further elucidate the mechanisms underlying the benefits of group-based exercises.\u003c/p\u003e\u003cp\u003eThis study has several notable strengths. First, it utilised a large nationally representative sample of Japanese adults, thereby enhancing the generalisability of the findings to a broader population. Second, both subjective (self-rated health) and objective (BMI) health indicators were simultaneously examined to provide a more comprehensive understanding of the health benefits of exercising with others. Third, by applying a counterfactual-based mediation framework, this study advances previous research by empirically testing the psychological and behavioural mechanisms underlying the association between group-based exercise and health outcomes.\u003c/p\u003e\u003cp\u003eHowever, this study has some limitations. Most importantly, the cross-sectional design precludes causal inference, and reverse causality cannot be ruled out; for instance, individuals with better health may be more inclined to participate in group-based exercise. Additionally, all variables, including BMI, exercise habits, and social interaction, were self-reported, which may have introduced recall and social desirability biases. The measure of social interaction was limited to general community interactions and may not have fully captured the quality or intensity of exercise-specific social associations. Furthermore, potential confounding factors, such as dietary patterns, personality traits (e.g. extraversion), and preexisting health conditions, were not assessed. These limitations should be addressed in future studies using longitudinal designs, objective measures of physical activity and health outcomes, and more refined assessments of social interaction.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eExercising with others contributes to improved subjective health, with particularly notable indirect effects through social interaction. In particular, its effectiveness in preventing underweight is important in Japan, as it provides insights for addressing public health challenges. Future health promotion policies can enhance not only the physical effects of exercise but also the initiatives that promote social interaction.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eInformed consent:\u003c/strong\u003e\u003cp\u003e No new informed consent was required for this secondary analysis of de-identified public-use data. The original survey was conducted by the Japan Sports Agency, and the publicly released dataset contains no directly identifying information.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eEthical approval:\u003c/strong\u003e\u003cp\u003e All analyses were conducted in accordance with institutional and national guidelines and with the principles of the 1964 Declaration of Helsinki and its later amendments, where applicable to anonymized secondary data. The primary survey was conducted by the Japan Sports Agency.\u003c/p\u003e\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eS.S. wrote the main manuscript text and M.M. revised. All authors reviewed the manuscript.\u003c/p\u003e\u003ch2\u003eData Availability\u003c/h2\u003e\u003cp\u003eAll data analyzed in this study are openly available from the Japan Sports Agency at: https://www.mext.go.jp/sports/b_menu/toukei/chousa04/sports/1415963_00008.htm.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eMiyachi M. Measures of physical activity and exercise for health promotion by the Ministry of Health, Labour and Welfare. J Phys Fit Sports Med. 2012;1(3):467\u0026ndash;72.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eShao T, Verma HK, Pande B, et al. Physical activity and nutritional influence on immune function: an important strategy to improve immunity and health status. 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Sci Rep. 2016;6:39151.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRyan RM, Deci EL. Intrinsic and extrinsic motivations: classic definitions and new directions. Contemp Educ Psychol. 2000;25(1):54\u0026ndash;67.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eSeino S, Kitamura A, Tomine Y, et al. Exercise arrangement is associated with physical and mental health in older adults. Med Sci Sports Exerc. 2019;51(6):1146\u0026ndash;53.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGolaszewski NM, LaCroix AZ, Hooker SP, et al. Exercising with others membership is associated with forms of social support, exercise identity, and amount of physical activity. Int J Sport Exerc Psychol. 2022;20(2):630\u0026ndash;43.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eTeixeira PJ, Carra\u0026ccedil;a EV, Markland D, et al. Exercise, physical activity, and self-determination theory: a systematic review. Int J Behav Nutr Phys Act. 2012;9:78.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eJapan Sports Agency. Public poll on sports participation 2022. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.mext.go.jp/sports/b_menu/toukei/chousa04/sports/1415963_00008.htm\u003c/span\u003e\u003cspan address=\"https://www.mext.go.jp/sports/b_menu/toukei/chousa04/sports/1415963_00008.htm\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. Accessed 22 October, 2025.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eJapan Society for the Study of Obesity. Guidelines for the management of obesity disease 2022. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.jasso.or.jp/contents/magazine/journal.html\u003c/span\u003e\u003cspan address=\"https://www.jasso.or.jp/contents/magazine/journal.html\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e. 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Effect of two choreographed fitness group-workouts on the body composition, cardiovascular and metabolic health of sedentary female workers. Int J Environ Res Public Health. 2019;16(24):4986.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eDavis AJ, MacCarron P, Cohen E. Social reward and support effects on exercise experiences and performance: evidence from parkrun. PLoS ONE. 2021;16(9):e0256546.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eKomatsu H, Yagasaki K, Saito Y, et al. Regular group exercise contributes to balanced health in older adults in Japan: a qualitative study. BMC Geriatr. 2017;17(1):190.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHerman CP. The social facilitation of eating: a review. Appetite. 2015;86:61\u0026ndash;73.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eVartanian LR, Spanos S, Herman CP, et al. Modeling of food intake: a meta-analytic review. Soc Influ. 2015;10(3):119\u0026ndash;36.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Social interaction, Mediation analysis, Subjective health, body mass index, Japan","lastPublishedDoi":"10.21203/rs.3.rs-8000528/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-8000528/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003e: Exercising with others has been shown to yield mental health benefits, particularly among older adults. However, evidence regarding physical health outcomes and younger populations in Japan remains limited. This study aimed to examine whether exercising with others is associated with better physical and subjective health among Japanese adults and to assess the mediating roles of social interaction and exercise habits.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003e: This study analysed cross-sectional data from 28,680 Japanese adults (mean age\u0026thinsp;=\u0026thinsp;50.2 years) who participated in the 2022 nationwide sports participation survey. Participants were classified into four groups: non-exercising, exercising alone, exercising with others, and mixed-type (both alone and with others). Logistic regression was used to assess associations between exercise type and health outcomes including underweight (body mass index\u0026thinsp;\u0026lt;\u0026thinsp;18.5 kg/m\u0026sup2;), obesity (body mass index\u0026thinsp;\u0026ge;\u0026thinsp;25 kg/m\u0026sup2;), and subjective health, adjusting for demographic variables. Mediation analyses evaluated indirect effects via social interaction and exercise habits.\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eCompared with exercising alone, exercising with others was associated with lower odds of being underweight and higher odds of reporting good subjective health. Similar trends were observed for mixed-type exercisers. No significant association was found with obesity. Mediation analyses revealed small but significant indirect effects on subjective health through social interaction, while direct effects remained substantial.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003eExercising with others is linked to improved subjective health and reduced risk of underweight among Japanese adults, partially mediated by social and behavioural factors. Promoting group-based exercise may be an effective public health strategy in Japan.\u003c/p\u003e","manuscriptTitle":"Benefits of exercising with others on physical and mental health in Japan: understanding the underlying mechanisms","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-19 09:18:34","doi":"10.21203/rs.3.rs-8000528/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"238cd914-0071-4c56-a6f4-e7dfdea324ce","owner":[],"postedDate":"November 19th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-02-16T16:01:03+00:00","versionOfRecord":{"articleIdentity":"rs-8000528","link":"https://doi.org/10.1007/s12529-026-10440-y","journal":{"identity":"international-journal-of-behavioral-medicine","isVorOnly":false,"title":"International Journal of Behavioral Medicine"},"publishedOn":"2026-02-10 15:57:29","publishedOnDateReadable":"February 10th, 2026"},"versionCreatedAt":"2025-11-19 09:18:34","video":"","vorDoi":"10.1007/s12529-026-10440-y","vorDoiUrl":"https://doi.org/10.1007/s12529-026-10440-y","workflowStages":[]},"version":"v1","identity":"rs-8000528","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-8000528","identity":"rs-8000528","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}