Differential impact of COVID-19 prevention and control measures on physical activity and mental health of junior high school students at different learning stages.

Objective: This study aimed to examine the differential associations of COVID-19 prevention and control measures on the physical activity levels (PALs) and mental health (MH) of middle school students at different learning stages. Additionally, it sought to provide evidence for designing interventions to promote adolescent physical activity (PA) and MH.

Methods: A cross-sectional survey was conducted over three years using the Physical Activity Questionnaire for Children and Adolescence (PAQ-CN) and the Mental Health Inventory of middle school students (MMHI-60) to assess PALs and MH. Analysis of variance (ANOVA) and cross-tabulation were employed to examine changes in PALs and MH over time.

Results: The PALs of adolescents were recorded as 2.51 ± 0.69 (95% CI: 2.47, 2.55) before the outbreak, 2.35 ± 0.74 (95% CI: 2.32, 2.39) during the outbreak, and 2.43 ± 0.71 (95% CI: 2.40, 2.47) after the easing of COVID-19 restrictions. Corresponding MH scores were 1.74 ± 0.63 (95% CI: 1.70, 1.77), 1.86 ± 0.73 (95% CI: 1.82, 1.90), and 1.77 ± 0.68 (95% CI: 1.73, 1.80), respectively. Significant changes were observed in both PALs and MH across the different periods (p < 0.01). The odds ratios for changes in these parameters were 28.60%, 35.30%, and 31.30%;The PALs of junior (7-9 grade) and senior (10-12 grade) high school students 2.66 ± 0.67, 2.57 ± 0.69, 2.49 ± 0.73 and 2.27 ± 0.65, 2.19 ± 0.73, 2.35 ± 0.69; the detection rates of psychological problems are 25.9%, 22.2%, 25.6% and 32.8%, 45.5%, 40.7%, respectively.

Conclusion: The impact of COVID-19 on the MH of middle school students varied across learning stages, the adverse effects of epidemic prevention and control on PAL and MH in senior high school students are greater than those in junior high school students, with younger age being a protective factor for both MH and PA. These findings highlight the importance of addressing the combined effects of learning pressures and the COVID-19 outbreak on the MH of Chinese adolescents.