Institute of Behavioural Sciences, University of Helsinki, 00014 Helsinki, Finland.
J Clin Endocrinol Metab. 2013 Apr;98(4):E619-27. doi: 10.1210/jc.2012-3745. Epub 2013 Mar 7.
Children who undertake more physical activity (PA) not only have more optimal physical health but also enjoy better mental health. However, the pathways by which PA affects well-being remain unclear.
To address this question, we examined whether objectively measured daytime PA was associated with diurnal hypothalamic-pituitary-adrenocortical axis (HPAA) activity and HPAA responses to psychosocial stress.
We conducted a cross-sectional study in a birth cohort in Helsinki, Finland.
We studied 258 8-year-old children.
PA was assessed with wrist-worn accelerometers. Overall PA and percentage of time spent in vigorous PA (VPA) were categorized by sex into thirds. Salivary cortisol was measured diurnally and in response to the Trier Social Stress Test for Children.
The children in different PA groups did not show differences in diurnal salivary cortisol (P > .10 for overall PA and VPA). Children with the highest levels of overall PA or VPA showed no, or only small, increases over time in salivary cortisol after stress (P = .10 and P =.03 for time in analyses of PA and VPA, respectively), whereas children belonging to the lowest and intermediate thirds showed significant increases over time in salivary cortisol after stress (P ≤ .002 for time in the analyses of overall PA and VPA).
These results suggest that children with lower levels of daytime PA have higher HPAA activity in response to stress. These findings may offer insight into the pathways of PA on physical and mental well-being.
进行更多身体活动（PA）的儿童不仅拥有更理想的身体健康，还享有更好的心理健康。然而，PA 影响健康的途径尚不清楚。
为了解决这个问题，我们研究了客观测量的日间 PA 是否与昼夜下丘脑-垂体-肾上腺轴（HPAA）活动以及 HPAA 对心理社会应激的反应有关。
我们在芬兰赫尔辛基的一个出生队列中进行了一项横断面研究。
我们研究了 258 名 8 岁儿童。
使用腕戴式加速度计评估 PA。总体 PA 和剧烈 PA（VPA）的时间百分比按性别分为三分之一。日间唾液皮质醇进行测量，并对儿童 Trier 社会应激测试进行反应。
不同 PA 组的儿童在日间唾液皮质醇方面没有差异（整体 PA 和 VPA 的 P >.10）。PA 或 VPA 水平最高的儿童在应激后唾液皮质醇的时间上没有增加，或者只有微小的增加（PA 和 VPA 的时间分析中 P =.10 和 P =.03），而属于最低和中间三分之一的儿童在应激后唾液皮质醇的时间上有明显增加（PA 和 VPA 的整体分析中 P ≤.002）。
这些结果表明，日间 PA 水平较低的儿童对压力的 HPAA 活动较高。这些发现可能为 PA 对身心健康的途径提供了深入了解。
