Bai Yang, Chen Senlin, Laurson Kelly R, Kim Youngwon, Saint-Maurice Pedro F, Welk Gregory J
Department of Kinesiology, Iowa State University, Ames, Iowa, United States of America.
School of Kinesiology and Recreation, Illinois State University, Normal, Illinois, United States of America.
PLoS One. 2016 Jan 28;11(1):e0148038. doi: 10.1371/journal.pone.0148038. eCollection 2016.
The purpose of the study is to examine the associations of youth physical activity and screen time with weight status and cardiorespiratory fitness in children and adolescents, separately, utilizing a nationally representative sample. A total of 1,113 participants (692 children aged 6-11 yrs; 422 adolescents aged 12-15 yrs) from the 2012 NHANES National Youth Fitness Survey. Participants completed physical activity and screen time questionnaires, and their body mass index and cardiorespiratory fitness (adolescents only) were assessed. Adolescents completed additional physical activity questions to estimate daily MET minutes. Children not meeting the screen time guideline had 1.69 times the odds of being overweight/obese compared to those meeting the screen time guideline, after adjusting for physical activity and other control variables. Among adolescent, screen time was significantly associated with being overweight/obese (odds ratio = 1.82, 95% confidence interval: 1.06-3.15), but the association attenuated toward the borderline of being significant after controlling for physical activity. Being physically active was positively associated with cardiorespiratory fitness, independent of screen time among adolescents. In joint association analysis, children who did not meet physical activity nor screen time guidelines had 2.52 times higher odds of being overweight/obese than children who met both guidelines. Adolescents who did not meet the screen time guideline had significantly higher odds ratio of being overweight/obese regardless of meeting the physical activity guideline. Meeting the physical activity guideline was also associated with cardiorespiratory fitness regardless of meeting the screen time guideline in adolescents. Screen time is a stronger factor than physical activity in predicting weight status in both children and adolescents, and only physical activity is strongly associated with cardiorespiratory fitness in adolescents.
本研究的目的是利用具有全国代表性的样本，分别考察儿童和青少年的身体活动及屏幕使用时间与体重状况和心肺适能之间的关联。共有1113名参与者（692名6至11岁儿童；422名12至15岁青少年）来自2012年美国国家健康与营养检查调查（NHANES）的全国青少年健身调查。参与者完成了身体活动和屏幕使用时间问卷，并对他们的体重指数和心肺适能（仅针对青少年）进行了评估。青少年还完成了额外的身体活动问题，以估算每日代谢当量分钟数。在对身体活动和其他控制变量进行调整后，未达到屏幕使用时间指南的儿童超重/肥胖的几率是达到指南的儿童的1.69倍。在青少年中，屏幕使用时间与超重/肥胖显著相关（优势比=1.82，95%置信区间：1.06-3.15），但在控制身体活动后，这种关联向显著边界减弱。在青少年中，身体活跃与心肺适能呈正相关，且与屏幕使用时间无关。在联合关联分析中，未达到身体活动和屏幕使用时间指南的儿童超重/肥胖的几率比同时达到两项指南的儿童高2.52倍。无论是否达到身体活动指南，未达到屏幕使用时间指南的青少年超重/肥胖的优势比显著更高。在青少年中，无论是否达到屏幕使用时间指南，达到身体活动指南也与心肺适能相关。在预测儿童和青少年的体重状况方面，屏幕使用时间比身体活动是更强的因素，而在青少年中，只有身体活动与心肺适能密切相关。
