Devís-Devís José, Lizandra Jorge, Valencia-Peris Alexandra, Pérez-Gimeno Esther, García-Massò Xavier, Peiró-Velert Carmen
Departament d'Educació Física i Esportiva, Universitat de València, Valencia, Spain.
Departament de Didàctica de l'Expressió Musical, Plàstica i Corporal, Universitat de València, Valencia, Spain.
PLoS One. 2017 Jun 21;12(6):e0179502. doi: 10.1371/journal.pone.0179502. eCollection 2017.
This study examined longitudinal changes in physical activity, sedentary behavior and body mass index in adolescents, specifically their migrations towards a different weight cluster. A cohort of 755 adolescents participated in a three-year study. A clustering Self-Organized Maps Analysis was performed to visualize changes in subjects' characteristics between the first and second assessment, and how adolescents were grouped. Also a classification tree was used to identify the behavioral characteristics of the groups that changed their weight cluster. Results indicated that boys were more active and less sedentary than girls. Boys were especially keen to technological-based activities while girls preferred social-based activities. A moderate competing effect between sedentary behaviors and physical activities was observed, especially in girls. Overweight and obesity were negatively associated with physical activity, although a small group of overweight/obese adolescents showed a positive relationship with vigorous physical activity. Cluster migrations indicated that 22.66% of adolescents changed their weight cluster to a lower category and none of them moved in the opposite direction. The behavioral characteristics of these adolescents did not support the hypothesis that the change to a lower weight cluster was a consequence of an increase in time devoted to physical activity or a decrease in time spent on sedentary behavior. Physical activity and sedentary behavior does not exert a substantial effect on overweight and obesity. Therefore, there are other ways of changing to a lower-weight status in adolescents apart from those in which physical activity and sedentary behavior are involved.
本研究调查了青少年身体活动、久坐行为和体重指数的纵向变化，特别是他们向不同体重组别的转变。755名青少年参与了一项为期三年的研究。进行了聚类自组织映射分析，以可视化第一次和第二次评估之间受试者特征的变化，以及青少年是如何分组的。还使用了分类树来识别改变体重组别的群体的行为特征。结果表明，男孩比女孩更活跃，久坐时间更少。男孩尤其热衷于基于技术的活动，而女孩则更喜欢基于社交的活动。观察到久坐行为和身体活动之间存在适度的竞争效应，尤其是在女孩中。超重和肥胖与身体活动呈负相关，尽管一小部分超重/肥胖青少年与剧烈身体活动呈正相关。聚类转变表明，22.66%的青少年将他们的体重组别转变为较低类别，且没有人向相反方向转变。这些青少年的行为特征并不支持以下假设：转变为较低体重组别是增加身体活动时间或减少久坐行为时间的结果。身体活动和久坐行为对超重和肥胖没有实质性影响。因此，除了涉及身体活动和久坐行为的方式外，青少年还有其他方式转变为较低体重状态。
