The relationship between behavior isotemporal substitution and depression among vocational school students with different moderate-to-vigorous physical activity durations

Abstract

Objective To explore the relationship between isotemporal substitution of 10 min/d of vigorous physical activity (VPA), moderate physical activity (MPA), walking, sedentary behavior (SB) and sleep (SLP) and depression among vocational school students with different duration of moderate-to-vigorous physical activity (MVPA), so as to provide time allocation suggestions for reducing depression levels.

Methods The convenient cluster sampling method was adopted to conduct a questionnaire survey among 8 149 grade one to grade three students in 14 vocational schools in Shanghai and Jiangsu Province from December 2021 to January 2022. According to whether the MVPA reached 60 min/d, the vocational school students were divided into the MVPA standard group and the MVPA non-standard group, and the isotemporal substitution model was used for analysis.

Results About 19.81% of students were in the MVPA standard group. In the MVPA non-standard group, substituting MPA for all other studied behaviors and substituting SLP for walking and SB were negatively correlated with depression (β = −0.78, −0.90, −0.88, −0.83; −0.07, −0.05, P<0.05), and the association of MPA substitution was much greater than that of SLP substitution. In the MVPA standard group, replacing VPA, walking and SB with SLP were all negatively associated with depression (β = −0.23, −0.12, −0.10), whereas replacing MPA, SB and SLP with VPA was all positively associated with depression (β = 0.15, 0.13, 0.23) ( P<0.05).

Conclusion The MVPA level of vocational school students is low. The effects of isotemporal substitution for VPA and MPA are different when MVPA duration is up to standard and when MVPA duration is not up to standard. Appropriate time allocation suggestions should be provided based on the characteristics of adolescents with different MVPA durations.

Abstract

【摘要】 目的 探索不同中髙强度体力活动 (MVPA) 时长职校学生 10 min/d 的髙强度体力活动 (VPA)、中强度体力活动 (MPA)、步行、久坐行为 (SB) 和睡眠 (SLP) 之间等时替代与抑郁的关系, 以期提供降低抑郁水平的时间分配建议。 方法 于 2021 年 12 月 一2022 年 1 月, 采用方便整群抽样法对上海和江苏共 14 所职校的 8 149 名一至三年级学生进行问卷调査。以 60 min/d 时长为界线, 将学生分为MVPA达标组和 MVPA 未达标组, 采用等时替代模型进行分析。 结果 MVPA 达标 组占 19.81%。在 MVPA 未达标组, 用 MPA 替代其他所有研究的行为 (β 值分别为 −0.78, −0.90, −0.88, −0.83)、及用 SLP 替 代步行和 SB (β 值分别为 −0.07, −0.05) 均与抑郁呈负相关 ( P 值均<0.05), 且 MPA 替代的关联大于 SLP 替代的关联; 在 MVPA 达标组, 用 SLP 替代 VPA、步行和 SB 均与抑郁呈负相关 (β 值分别为 −0.23, −0.12, −0.10), 而用 VPA 替代 MPA, SB 和 SLP 均与抑郁呈正相关 (β 值分别为 0.15, 0.13, 0.23) ( P 值均<0.05)。 结论 职校学生 MVPA 水平较低; 在 MVPA 达标 时和未达标时, VPA 和 MPA 等时替代的效应不同。应根据不同 MVPA 时长青少年的特点提供合适的时间分配建议。