Department of Coaching and Psychology, Norwegian School of Sport Sciences, Oslo, Norway.
Int J Behav Nutr Phys Act. 2012 May 29;9:63. doi: 10.1186/1479-5868-9-63.
There is limited knowledge as to whether obesity prevention interventions are able to produce change in the determinants hypothesized to precede change in energy balance-related behaviors in young people. The aim of this study was to evaluate the effect of a multi-component intervention on a wide range of theoretically informed determinants of physical activity (PA) and sedentary behavior (SB). Moderation effects of gender, weight status and parental education level and whether the perceived intervention dose received influenced the effects were also explored.
The HEIA study was a 20-month school-based, randomized controlled trial to promote healthy weight development. In total, 1418 11-year-olds participated at baseline and post-intervention assessment. Enjoyment, self-efficacy, perceived social support from parents, teachers and friends related to PA, perceived parental regulation of TV-viewing and computer/game-use and perceived social inclusion at schools were examined by covariance analyses to assess overall effects and moderation by gender, weight status and parental education, mid-way and post-intervention. Covariance analyses were also used to examine the role of intervention dose received on change in the determinants.
At mid-way enjoyment (p = .03), perceived social support from teachers (p = .003) and self-efficacy (p = .05) were higher in the intervention group. Weight status moderated the effect on self-efficacy, with a positive effect observed among the normal weight only. At post-intervention results were sustained for social support from teachers (p = .001), while a negative effect was found for self-efficacy (p = .02). Weight status moderated the effect on enjoyment, with reduced enjoyment observed among the overweight. Moderation effects for parental education level were detected for perceived social support from parents and teachers. Finally, positive effects on several determinants were observed among those receiving a high as opposed to a low intervention dose.
The intervention affected both psychological and social-environmental determinants. Results indicate that social support from teachers might be a potential mediator of PA change, and that overweight adolescents might be in need of specially targeted interventions to avoid reducing their enjoyment of PA. Further studies should continue to assess how intervention effectiveness is influenced by the participants' self-reported dose of intervention received.
目前对于肥胖预防干预措施是否能够改变年轻人能量平衡相关行为之前的决定因素知之甚少。本研究旨在评估一种多组分干预措施对广泛的体力活动（PA）和久坐行为（SB）理论上有影响的决定因素的效果。还探讨了性别、体重状况和父母教育水平的调节作用，以及感知到的干预剂量是否会影响效果。
HEIA 研究是一项为期 20 个月的以学校为基础的随机对照试验，旨在促进健康体重发育。共有 1418 名 11 岁儿童在基线和干预后评估时参与了研究。通过协方差分析来评估对 PA 的喜爱程度、自我效能感、感知到的来自父母、老师和朋友的社会支持、感知到的父母对看电视和玩电脑游戏的调节以及在学校的社会包容度，以评估整体效果和性别、体重状况和父母教育的调节作用，以及干预过程中的中间和后期。还使用协方差分析来检验所接受的干预剂量对决定因素变化的作用。
在中期，干预组的喜爱程度（p = .03）、感知到的来自老师的社会支持（p = .003）和自我效能感（p = .05）更高。体重状况调节了自我效能感的影响，仅在正常体重的儿童中观察到积极的影响。在干预后，结果仍然持续，来自老师的社会支持（p = .001），而自我效能感则出现了负向影响（p = .02）。体重状况调节了喜爱程度的影响，超重儿童的喜爱程度降低。感知到的来自父母和老师的社会支持方面检测到了父母教育水平的调节作用。最后，在接受高剂量干预的人群中，观察到对几个决定因素的积极影响，而不是低剂量干预。
该干预措施影响了心理和社会环境决定因素。结果表明，来自老师的社会支持可能是 PA 变化的潜在中介，超重青少年可能需要特别有针对性的干预措施，以避免降低他们对 PA 的喜爱程度。应进一步研究如何通过参与者自我报告的干预剂量来影响干预效果。
