Atkin Andrew J, Sherar Lauren B, Ekelund Ulf, Hansen Bjorge H, Andersen Lars Bo, Anderssen Sigmund, Kriemler Susi, Kwon Soyang, Kristensen Peter L, Wedderopp Niels, Northstone Kate, Jago Russell, Pate Russell, Puder Jardena J, Salmon Jo, Sardinha Luis B, van Sluijs Esther M F
School of Health Sciences, Faculty of Medicine and Health Sciences, University of East Anglia, Norwich, United Kingdom.
MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Institute of Metabolic Science, Cambridge Biomedical Campus, Cambridge, United Kingdom.
PLoS One. 2025 Sep 10;20(9):e0327394. doi: 10.1371/journal.pone.0327394. eCollection 2025.
Many young people fail to achieve the minimum recommended amount of physical activity to benefit their health. Understanding the nature of age-related changes in behaviour and how this varies for population sub-groups is informative for intervention design. The aim of this study was to describe age-related changes in physical activity and sedentary time and examine variability in patterns of change across demographic sub-groups.
Data are from 13 studies in the International Children's Accelerometry Database (ICAD), all of which provided ≥2 waves of waist-worn accelerometer data. Annual change in sedentary time, light intensity physical activity (LPA) and moderate to vigorous intensity physical activity (MVPA) were estimated using three level mixed effects linear regression models, using participant age as the exposure variable. In interaction models, we examined whether changes in behaviour differed by day of the week (weekday/ weekend), age at baseline assessment (<10/ ≥ 10 years), sex, weight category, maternal education and ethnicity.
In total, 6567 participants provided two or more waves of valid accelerometer data (44.5% boys, mean (SD) baseline age 10.6 (2.1) years (range 4.1-15.8 years)). Across the week and for all studied sub-groups, sedentary time increased by approximately 25 minutes/day/year of age, LPA decreased by approximately 22 minutes/day/year of age and MVPA decreased by approximately 3 minutes/day/year of age. The annual increase in sedentary time was greater in girls compared to boys (β (95% confidence interval) change (min) for each additional year of age: girls, 25.9 (25.4, 26.4); boys, 23.6 (23.0, 24.2)) and in adolescents compared to children (adolescents, 27.0 (26.5, 27.6); children, (23.5 (22.9, 24.2)). The annual decrease in MVPA was greater in boys compared to girls (boys, -2.7 (-3.0, -2.5); girls, -2.2 (-2.4, -2.0)) and at the weekend compared to during the week (weekend, -3.0 (-3.3, -2.8); weekday -2.3 (-2.5, -2.1)).
Accelerometer assessed sedentary time increased whilst LPA and MVPA decreased during childhood and adolescence. This overall pattern was observed across the week and in all studied sub-groups, but small differences in the magnitude of changes can be used to guide the timing and targeting of behaviour change interventions, such as designing physical activity interventions which focus on weekends where a child's time is less structured.
许多年轻人未能达到有益健康的最低推荐运动量。了解与年龄相关的行为变化的本质以及不同人群亚组之间的差异，对于干预措施的设计具有指导意义。本研究的目的是描述与年龄相关的身体活动和久坐时间的变化，并研究不同人口统计学亚组变化模式的差异。
数据来自国际儿童加速度计数据库（ICAD）中的13项研究，所有研究均提供了≥2次佩戴在腰部的加速度计数据。使用三级混合效应线性回归模型，以参与者年龄作为暴露变量，估计久坐时间、轻度身体活动（LPA）和中度至剧烈身体活动（MVPA）的年度变化。在交互模型中，我们研究了行为变化在一周中的不同日期（工作日/周末）、基线评估时的年龄（<10岁/≥10岁）、性别、体重类别、母亲教育程度和种族方面是否存在差异。
共有6567名参与者提供了两波或更多波有效的加速度计数据（44.5%为男孩，平均（标准差）基线年龄10.6（2.1）岁（范围4.1 - 15.8岁））。在一周内以及所有研究的亚组中，久坐时间每年增加约25分钟/天/岁，LPA每年减少约22分钟/天/岁，MVPA每年减少约3分钟/天/岁。女孩久坐时间的年增加量大于男孩（每增加一岁的β（95%置信区间）变化（分钟）：女孩，25.9（25.4，26.4）；男孩，23.6（23.0，24.2）），青少年的久坐时间年增加量大于儿童（青少年，27.0（26.5，27.6）；儿童，23.5（22.9，24.2））。男孩MVPA的年减少量大于女孩（男孩，- 2.7（- 3.0，- 2.5）；女孩，- 2.2（- 2.4，- 2.0）），周末的MVPA年减少量大于工作日（周末，- 3.0（- 3.3，- 2.8）；工作日，- 2.3（- 2.5，- 2.1））。
加速度计评估显示，在儿童期和青少年期，久坐时间增加，而LPA和MVPA减少。这种总体模式在一周内以及所有研究的亚组中均有观察到，但变化幅度的细微差异可用于指导行为改变干预措施的时机和目标设定，例如设计侧重于周末的身体活动干预措施，因为儿童在周末的时间安排较不规律。
