J Phys Act Health. 2020 Jan 1;17(1):45-51. doi: 10.1123/jpah.2019-0207.
Little is known about how daily fluctuations in health behaviors relate to chronic disease risk. The goal of this study was to examine whether variability in physical activity, caloric intake, and sleep is related to body composition (body mass index and body fat percentage).
Healthy adults (N = 103; 64% female) were monitored for 7 days to assess physical activity (SenseWear Armband), caloric intake (daily food diaries), and sleep duration and timing (Actiwatch Spectrum). Data were analyzed using correlations (between- and within-subjects correlations) and regression.
The results demonstrated that variabilities in physical activity, caloric intake, and sleep were unrelated. Caloric intake and sleep variability were unrelated to body composition. At greater levels of physical activity variability, any level of physical activity was protective for body composition.
These results suggest that among healthy adults, variabilities in health behaviors may be independent of each other, and physical activity variability may be more strongly related to body composition among those who are less active.
人们对于健康行为的日常波动与慢性病风险之间的关系知之甚少。本研究的目的是检验体力活动、热量摄入和睡眠的变化是否与身体成分（体重指数和体脂百分比）有关。
健康成年人（N=103；64%为女性）被监测了 7 天，以评估体力活动（SenseWear 臂带）、热量摄入（每日食物日记）和睡眠持续时间和时间（Actiwatch Spectrum）。使用相关性（组内和组间相关性）和回归进行数据分析。
结果表明，体力活动、热量摄入和睡眠的变化之间没有关系。热量摄入和睡眠变化与身体成分无关。在更高水平的体力活动变化中，任何水平的体力活动都对身体成分有保护作用。
这些结果表明，在健康成年人中，健康行为的变化可能相互独立，而体力活动的变化可能与那些不太活跃的人的身体成分更为相关。
