Factors associated with adherence to muscle-trengthening activity guidelines among adolescents at different...

This study aimed to examine the associations between guideline-concordant muscle-strengthening activity (MSA) and multiple factors, including anthropometric measures, demographic characteristics, behavioral patterns, and sociocultural influences, across different educational stages among Chinese school-aged children.

Utilizing data from the 2019 Shanghai Student Physical Fitness Index Survey, we analyzed a representative sample of 81,264 school children (aged 9-17 years; 49.6% female) and their parents. Participants reporting ≥ 3 days of MSA per week were classified as meeting the MSA recommendations. Student-reported measures included gender, grade level, MSA frequency, moderate-to-vigorous physical activity (MVPA), peer and parental support, and anthropometric data for BMI calculation. Parent-reported measures encompassed family income and parental MSA/MVPA participation. Binary logistic regression was employed to identify factors associated with meeting the MSA recommendations.

The analysis revealed that 51.2% of Shanghai school children met MSA recommendations, but participation rates varied significantly by grade level. In the elementary school model, student MVPA (school days: OR = 1.77, 95% CI:1.74-1.81; weekends: OR = 1.84, 95% CI:1.76-1.93), parental MSA (OR = 1.14, 95% CI:1.11-1.16), peer support (OR = 1.07, 95% CI:1.06-1.09) and family income (30,0001-10,0000) (OR = 1.08, 95% CI:1.0-1.18) were significantly associated with guideline-concordant MSA, explaining 72.5% of the variance. The middle school model additionally identified parental support as a significant predictor (junior middle: OR = 1.01, 95% CI:1.00-1.01; junior high: OR = 1.02, 95% CI:1.01-1.02), accounting for 68.6% and 70.8% of the variance, respectively.

Our findings advance the understanding of MSA behavior among Chinese youth and its grade-specific determinants. The results suggest that effective interventions should adopt a multi-level approach, engaging not only the children themselves but also their parents and peers to promote healthier, more active lifestyles.