Faculty of Kinesiology, University of New Brunswick, New Brunswick, Canada.
Cardiometabolic Exercise & Lifestyle Laboratory, Faculty of Kinesiology, University of New Brunswick, New Brunswick, Canada.
Sci Rep. 2021 Sep 28;11(1):19211. doi: 10.1038/s41598-021-98731-0.
Physical activity (PA) is critical to improving health factors such as weight, adiposity, and aerobic fitness. However, children who meet PA guideline recommendations demonstrate developmental differences in health-related outcomes. To investigate prospective associations between PA behaviour (overall PA and PA intensity) and trajectories of health-related factors among physically active children. This prospective study (2.5 years) included 391 children (baseline age: 8.1 ± 1.4 years; girls 36.3%) from ten public schools. All children performed 60-min or more of moderate-to-vigorous physical activity (MVPA) per day objectively measured. Trajectories of BMI, waist circumference, and aerobic fitness were constructed with a group-based multi-trajectory model. Three trajectory subgroups were identified: 'high fitness/normal weight' (48.4% of children), 'moderate fitness /normal weight' (42.5% of children), and 'low fitness/overweight-obese' (9.1% of children). Children performing higher overall PA, were less likely of being classified as members of the 'Low Fitness/Overweight-Obese' [Relative Risk Ratio (RRR and 95% CI) = 0.56 (0.37 to 0.85) compared to 'high fitness/normal weight' subgroup. Each additional 5% in light PA time was associated with approximately twofold [RRR 2.12 (1.24-3.61)] increased risk of being in the 'low fitness/overweight-obese' trajectory relative to the 'high fitness/normal weight' trajectory. Each additional 2% in vigorous-PA time was associated with a 42% and 85% reduced risk (relative to 'high fitness/normal weight') of being in the 'moderate fitness/normal weight' [RRR 0.58 (0.38-0.96)] and 'low fitness/overweight-obesity' [RRR 0.15 (0.06-0.37)] trajectory, respectively. Overall PA and additional time in vigorous-PA was associated with improved health-related outcomes, while light PA was negatively associated with health-related outcomes among children who adhere to PA guideline recommendations. Vigorous PA was the strongest predictor of the health trajectories. All PA guidelines for children should place greater emphasis on the importance of vigorous PA.
身体活动（PA）对于改善体重、肥胖和有氧适能等健康因素至关重要。然而，达到 PA 指南推荐标准的儿童在健康相关结果方面表现出发展差异。本前瞻性研究（2.5 年）纳入了来自十所公立学校的 391 名儿童（基线年龄：8.1±1.4 岁；女孩占 36.3%）。所有儿童均通过客观测量每天进行 60 分钟或更长时间的中等到剧烈身体活动（MVPA）。使用基于群组的多轨迹模型构建 BMI、腰围和有氧适能的轨迹。确定了三个轨迹亚组：“高体能/正常体重”（48.4%的儿童）、“中体能/正常体重”（42.5%的儿童）和“低体能/超重肥胖”（9.1%的儿童）。进行更高水平总体 PA 的儿童不太可能被归类为“低体能/超重肥胖”组的成员[相对风险比（RRR 和 95%CI）=0.56（0.37 至 0.85），与“高体能/正常体重”亚组相比]。每增加 5%的低强度 PA 时间与大约两倍[RRR 2.12（1.24 至 3.61）]的风险相关，即在“低体能/超重肥胖”轨迹中，而不是在“高体能/正常体重”轨迹中。每增加 2%的剧烈 PA 时间与降低 42%和 85%的风险相关（与“高体能/正常体重”相比），分别处于“中体能/正常体重”[RRR 0.58（0.38 至 0.96）]和“低体能/超重肥胖”[RRR 0.15（0.06 至 0.37）]轨迹中。总体 PA 和剧烈 PA 时间的增加与健康相关结果的改善有关，而低强度 PA 与遵守 PA 指南建议的儿童的健康相关结果呈负相关。剧烈 PA 是健康轨迹的最强预测因子。所有儿童 PA 指南都应更加重视剧烈 PA 的重要性。
