Mingyuan Dong ¹ Mingtian Niu ^2* Yongchul Choi ¹ Ning Li ³

• ¹ Department of Physical Education, Gangneung–Wonju National University, Gangneung, Republic of Korea
• ² Department of Public Physical Education, Xinyang College, Xinyang, China
• ³ School of Computer Science, Wuhan University, Wuhan, Hubei Province, China

Background: Social support has been identified as a key factor influencing adolescents' engagement in physical activities. However, the relationship between middle school girls’ physical activity levels and the actual social support they receive remains unclear. Aim: This study aims to explore the support mechanisms that promote increased physical activity participation among middle school girls. Methods: A survey was conducted with 1,371 middle school girls from 16 regions and cities in China. The questionnaire included the Physical Activity Questionnaire (PAQ), the Social Support and Exercise Survey, the Physical Activity Rank Scale, and the Family Affluence Scale (FAS). Linear regression was used to examine the relationships among family support, out-of-school exercise behavior, in-school exercise behavior, and the physical activity levels of middle school girls. Results: In-school physical activity participation (6.6%) was higher than out-of-school participation (5.5%) among urban middle school girls. Physical activity levels were significantly positively correlated with social support from family, peers, and teachers (p < 0.01). Linear regression and descriptive statistics consistently showed that family support was the highest (3.50 ± 1.06), followed by teacher support (3.17 ± 0.96) and peer support (2.88 ± 0.96). Emotional support was notably higher, while instrumental support was relatively low. The physical activity levels of urban middle school girls were associated with the age and grade of the individual, the economic conditions of the family, and the highest level of education of the parents. Conclusions: Family support significantly enhances urban middle school girls’ participation in physical activities. Higher parental education levels may reduce girls’ activity participation, while improved family economic conditions may decrease emotional support but increase informational support. The support of friends and teachers will make up for the decrease in family support. A school-based social support network is essential to address disparities in activity support and implement health intervention programs for middle school girls.