Petersen L, Schnohr P, Sørensen T I A
Danish Epidemiology Science Centre at Institute of Preventive Medicine, Copenhagen University Hospital, Copenhagen K DK-1399, Denmark.
Int J Obes Relat Metab Disord. 2004 Jan;28(1):105-12. doi: 10.1038/sj.ijo.0802548.
Earlier observational studies of the relation between physical activity and obesity are inconsistent and ambiguous, showing a clear cross-sectional inverse relation, and a prospective association only when physical activity at the time of follow-up is included.
To examine the long-term effect of leisure time physical activity (LTPA) on subsequent development of obesity and the effect of body weight on later physical inactivity in a population-based longitudinal setting taking into account the effects of historical changes on future changes as well as pertinent confounders.
The study included 3653 women and 2626 men aged 20-78 y selected at random within sex-age strata from the general population of Copenhagen. At two surveys, 5 y apart, LTPA, body mass index (BMI) (weight/height2, kg/m2), several possible confounders and modifying factors were assessed. Obesity (defined as BMI > or =30 kg/m2) and LTPA was assessed at the 3rd survey 10 y later. Odds ratios (with 95% confidence limits) for developing obesity between the last two surveys were estimated by logistic regression analysis, taking into account baseline and preceding changes in BMI and LTPA. A similar analysis of odds ratios for physical inactivity as outcome at the 3rd survey was conducted.
Compared to physical inactivity, the odds ratios of development of obesity among women with medium and high level of activity were 0.81 (0.53, 1.25) and 1.16 (0.73, 1.84), respectively, and among men, the odds ratios were 1.28 (0.71, 2.33) and 1.65 (0.91, 2.99), respectively. Compared to median BMI, the odds ratio of later physical inactivity among women with high BMI was 1.91 (1.39, 2.61), and among men the odds ratio was 1.50 (1.01, 2.22). The associations were not confounded or modified by age, pre-existing diseases, smoking, alcohol intake, educational level, occupational physical activity or by familial predisposition to obesity.
This study did not support that physical inactivity as reported in the freely living adult population in the long term is associated with the development of obesity, but the study indicates that obesity may lead to physical inactivity.
早期关于体力活动与肥胖关系的观察性研究结果并不一致且含混不清，呈现出明显的横断面负相关关系，只有在纳入随访时的体力活动情况后才显示出前瞻性关联。
在基于人群的纵向研究中，考虑历史变化对未来变化的影响以及相关混杂因素，研究休闲时间体力活动（LTPA）对后续肥胖发生的长期影响，以及体重对后期体力活动不足的影响。
该研究从哥本哈根普通人群的性别 - 年龄分层中随机选取了3653名20 - 78岁的女性和2626名男性。在相隔5年的两次调查中，评估了LTPA、体重指数（BMI）（体重/身高²，kg/m²）、几个可能的混杂因素和修正因素。在10年后的第三次调查中评估肥胖（定义为BMI≥30 kg/m²）和LTPA。通过逻辑回归分析估计最后两次调查之间发生肥胖的比值比（及其95%置信区间），同时考虑BMI和LTPA的基线及先前变化情况。对第三次调查中以体力活动不足为结局的比值比进行了类似分析。
与体力活动不足相比，中等和高水平活动的女性发生肥胖的比值比分别为0.81（0.53，1.25）和1.16（0.73，1.84），男性的比值比分别为1.28（0.71，2.33）和1.65（0.91，2.99）。与BMI中位数相比，高BMI女性后期体力活动不足的比值比为1.91（1.39，2.61），男性的比值比为1.50（1.01，2.22）。这些关联未被年龄、既往疾病、吸烟、饮酒、教育水平、职业体力活动或肥胖家族易感性所混淆或修正。
本研究不支持长期来看自由生活的成年人群中报告的体力活动不足与肥胖发生相关，但该研究表明肥胖可能导致体力活动不足。
