Wittmeier Kristy D M, Mollard Rebecca C, Kriellaars Dean J
Human Performance Laboratory, School of Medical Rehabilitation, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.
Obesity (Silver Spring). 2008 Feb;16(2):415-20. doi: 10.1038/oby.2007.73.
Physical activity recommendations for children focus on duration of activity and underemphasize intensity.
To evaluate the relationship between physical activity (intensity and duration) and the odds of being overweight, >20% body fat and >25% body fat.
Body fat, BMI and physical activity (accelerometry) were measured in children (n = 251) aged 8-10 years. Physical activity was quantified as time in moderate physical activity (MPA) and vigorous physical activity (VPA).
Prevalence of overweight and obesity were 18 and 11.6%, respectively. Regression indicated that VPA, not MPA, is associated with body fat (r = 0.35, P < 0.001) and BMI (r = 0.26, P < 0.001). Odds ratio demonstrated a significant impact of MPA and VPA on body composition. Children performing < or =5 min/day of VPA are 4.0 times more likely to have > or =20% body fat (P < 0.001), 2.9 times more likely to have > or =25% body fat (P < 0.05) and 5.2 times more likely to be classified as overweight (P < 0.01) compared to children performing > or =15 min/day. Those performing < or =15 min/day of MPA vs. >45 min/day MPA are at 4.2 increased odds of having > or =20% body fat (P < 0.001), and 3.0 increased odds of having > or =25% (P < 0.01).
Lower durations of both MPA and VPA are associated with increased odds of overweight and adiposity. Forty-five minutes of MPA and fifteen minutes of VPA were associated with reduced body fat and BMI. We recommend that these amounts are used to develop minimum physical activity intensity guidelines for the prevention and treatment of obesity.
针对儿童的体育活动建议侧重于活动时长，而对强度的强调不足。
评估体育活动（强度和时长）与超重、体脂率>20%和体脂率>25%几率之间的关系。
对251名8至10岁儿童测量了体脂、体重指数（BMI）和体育活动情况（通过加速度计测量）。体育活动量化为中等强度体育活动（MPA）和高强度体育活动（VPA）的时长。
超重和肥胖的患病率分别为18%和11.6%。回归分析表明，与体脂（r = 0.35，P < 0.001）和BMI（r = 0.26，P < 0.001）相关的是VPA，而非MPA。优势比表明MPA和VPA对身体成分有显著影响。与每天进行≥15分钟VPA的儿童相比，每天进行≤5分钟VPA的儿童体脂率≥20%的可能性高4.0倍（P < 0.001），体脂率≥25%的可能性高2.9倍（P < 0.05），被归类为超重的可能性高5.2倍（P < 0.01）。与每天进行>45分钟MPA相比，每天进行≤15分钟MPA的儿童体脂率≥20%的几率增加4.2倍（P < 0.001），体脂率≥25%的几率增加3.0倍（P < 0.01）。
MPA和VPA时长较短均与超重和肥胖几率增加有关。45分钟的MPA和15分钟的VPA与较低的体脂率和BMI相关。我们建议将这些时长用于制定预防和治疗肥胖的最低体育活动强度指南。
