Institute for Physical Activity and Nutrition (IPAN), School of Exercise and Nutrition Sciences, Deakin University, 221 Burwood Highway, Geelong, Victoria, Australia.
Alliance for Research in Exercise, Nutrition and Activity (ARENA), Allied Health and Human Performance, University of South Australia, Adelaide, South Australia, Australia.
BMC Public Health. 2024 Apr 12;24(1):1015. doi: 10.1186/s12889-024-18495-w.
There is limited evidence of the associations between postural-derived sitting time, waist-worn derived sedentary time and children's health and the moderation effect of physical activity (PA). This study examined associations of children's device-measured sitting time with cardiometabolic health risk factors, including moderation by physical activity.
Cross-sectional baseline data from children (mean-age 8.2 ± 0.5 years) in Melbourne, Australia (2010) participating in the TransformUs program were used. Children simultaneously wore an activPAL to assess sitting time and an ActiGraph GT3X to assess sedentary time and physical activity intensity. Cardiometabolic health risk factors included: adiposity (body mass index [BMI], waist circumference [WC]), systolic and diastolic blood pressure (SBP, DBP), high-density lipoprotein (HDL), low-density lipoprotein (LDL), cholesterol, triglycerides, fasting plasma glucose (FPG), serum insulin, and 25-hydroxyvitaminD (25[OH]D). Linear regression models (n = 71-113) assessed associations between sitting time with each health risk factor, adjusted for different PA intensities (i.e. light [LIPA], moderate-vigorous intensities [MVPA], separately on each model), age, sex, adiposity, and clustering by school. Interaction terms examined moderation. The analyses were repeated using device-measured sedentary time (i.e. ActiGraph GT3X) for comparison.
Sitting time was positively associated with SBP (b = 0.015; 95%CI: 0.004, 0.026), DBP (b = 0.012; 95%CI:0.004, 0.020), and FPG (b = 0.001; 95%CI: 0.000, 0.000), after adjusting for higher PA intensities. The association between sitting time and insulin (b = 0.003; 95%CI: 0.000, 0.006) was attenuated after adjusting for higher PA intensities. When the models were adjusted for LIPA and MVPA, there was a negative association with LDL (b=-0.001; 95%CI: -0.002, -0.000 and b=-0.001; 95%CI: -0.003, -0.000, respectively). There was a negative association of sedentary time with WCz (b=-0.003; 95%CI: -0.005, 0.000) and BMIz (b=-0.003; 95%CI: -0.006, -0.000) when the models were adjusted by MVPA. Sedentary time was positively associated with triglycerides (b = 0.001; 95%CI: 0.000, 0.001) but attenuated after adjusting for MVPA. No evidence of moderation effects was found.
Higher volumes of sitting and sedentary time were associated with some adverse associations on some cardiometabolic health risk factors in children. These associations were more evident when sitting time was the predictor. This suggests that reducing time spent sitting may benefit some cardiometabolic health outcomes, but future experimental research is needed to confirm causal relationships and identify the biological mechanisms that might be involved.
Australian New Zealand Clinical Trials Registry: ACTRN12609000715279.
关于姿势性久坐时间、腰部佩戴设备记录的久坐时间与儿童健康之间的关联，以及体力活动（PA）的调节作用，证据有限。本研究通过设备测量了儿童的久坐时间，评估了其与心血管代谢健康风险因素的关联，包括体力活动的调节作用。
本研究使用了来自澳大利亚墨尔本（2010 年）TransformUs 项目的儿童（平均年龄 8.2±0.5 岁）的基线横断面数据。儿童同时佩戴 activPAL 以评估坐姿时间，佩戴 ActiGraph GT3X 以评估久坐时间和体力活动强度。心血管代谢健康风险因素包括：肥胖（体重指数 [BMI]、腰围 [WC]）、收缩压和舒张压（SBP、DBP）、高密度脂蛋白（HDL）、低密度脂蛋白（LDL）、胆固醇、甘油三酯、空腹血糖（FPG）、血清胰岛素和 25-羟维生素 D（25[OH]D）。线性回归模型（n=71-113）评估了坐姿时间与每个健康风险因素之间的关联，模型调整了不同的 PA 强度（即轻强度 PA [LIPA]、中高强度 PA [MVPA]，分别在每个模型中）、年龄、性别、肥胖和按学校聚类。交互项检验了调节作用。使用设备测量的久坐时间（即 ActiGraph GT3X）进行了比较，重复了分析。
在调整较高的 PA 强度后，坐姿时间与 SBP（b=0.015；95%CI：0.004，0.026）、DBP（b=0.012；95%CI：0.004，0.020）和 FPG（b=0.001；95%CI：0.000，0.000）呈正相关。在调整较高的 PA 强度后，坐姿时间与胰岛素（b=0.003；95%CI：0.000，0.006）之间的关联减弱。当模型调整为 LIPA 和 MVPA 时，LDL（b=-0.001；95%CI：-0.002，-0.000 和 b=-0.001；95%CI：-0.003，-0.000）呈负相关。当模型按 MVPA 调整时，久坐时间与 WCz（b=-0.003；95%CI：-0.005，0.000）和 BMIz（b=-0.003；95%CI：-0.006，-0.000）呈负相关。在调整 MVPA 后，久坐时间与甘油三酯（b=0.001；95%CI：0.000，0.001）呈正相关，但这种相关性减弱。没有发现调节作用的证据。
较高的坐姿和久坐时间与儿童一些心血管代谢健康风险因素的一些不良关联有关。当坐姿时间是预测因素时，这些关联更为明显。这表明减少坐姿时间可能有益于一些心血管代谢健康结果，但需要进一步的实验研究来确认因果关系，并确定可能涉及的生物学机制。
澳大利亚新西兰临床试验注册处：ACTRN12609000715279。
