Huppertz C, Bartels M, van Beijsterveldt C E M, Willemsen G, Hudziak J J, de Geus E J C
Department of Biological Psychology VU University Amsterdam Amsterdam The Netherlands.
EMGO+ Institute for Health and Care Research VU University Medical Center Amsterdam The Netherlands.
Obes Sci Pract. 2015 Sep 15;1(1):1-11. doi: 10.1002/osp4.2. eCollection 2015 Oct.
This population-based study aimed (1) to test the presence of an association between regular voluntary exercise behaviour (EB) that is performed in leisure time and body mass index (BMI) in youth and (2) to investigate the causal nature of this association using a longitudinal design in genetically informative subjects.
Both EB and BMI were assessed repeatedly over time in 21 458 twin individuals from the Netherlands Twin Register (47.5% male) - first by parental report (ages 7, 10 and 12) and subsequently through self-report surveys (ages 14, 16 and 18). EB was quantified as weekly metabolic equivalent of task hours.
Correlations over time were higher for BMI than for EB ( ≈ 0.70 vs. ≈ 0.35) across 12 different follow-up periods. Cross-sectionally, regular involvement in EB was not associated with lower BMI in childhood and in genetically identical twin pairs discordant for EB; the exercising twin did not have a lower BMI than the non-exercising twin. Longitudinally, linear and quadratic relationships between EB and BMI were non-significant. Changes in EB over time did not induce opposite changes in BMI.
No consistent association between regular EB and BMI was observed from ages 7 to 18 years.
这项基于人群的研究旨在（1）检验青少年闲暇时间进行的规律自愿运动行为（EB）与体重指数（BMI）之间是否存在关联，以及（2）在具有遗传信息的受试者中采用纵向设计来研究这种关联的因果性质。
对来自荷兰双胞胎登记处的21458名双胞胎个体（47.5%为男性）的EB和BMI随时间进行多次评估——首先通过父母报告（7岁、10岁和12岁时），随后通过自我报告调查（14岁、16岁和18岁时）。EB被量化为每周代谢当量任务小时数。
在12个不同的随访期内，BMI随时间的相关性高于EB（约0.70对约0.35）。横断面研究中，在童年时期以及在EB不一致的同卵双胞胎对中，规律参与EB与较低的BMI无关；运动的双胞胎的BMI并不低于不运动的双胞胎。纵向研究中，EB与BMI之间的线性和二次关系不显著。EB随时间的变化并未引起BMI的相反变化。
在7至18岁之间未观察到规律的EB与BMI之间存在一致的关联。
