Gaudet Jeffrey, Gallant François, Bélanger Mathieu
Centre de formation médicale du Nouveau-Brunswick, Moncton, NB, Canada.
Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, NB, Canada.
JMIR Mhealth Uhealth. 2017 Jul 6;5(7):e92. doi: 10.2196/mhealth.7647.
Only 5% of Canadian youth meet the recommended 60 minutes of moderate to vigorous physical activity (MVPA) per day, with leisure time being increasingly allocated to technology usage. Direct-to-consumer mHealth devices that promote physical activity, such as wrist-worn physical activity trackers, have features with potential appeal to youth.
The primary purpose of this study was to determine whether a minimalist physical activity tracker-based intervention would lead to an increase in physical activity in young adolescents. A secondary aim of this study was to assess change in physical activity across a 7-week intervention, as measured by the tracker.
Using a quasi-experimental crossover design, two groups of 23 young adolescents (aged 13-14 years) were randomly assigned to immediate intervention or delayed intervention. The intervention consisted of wearing a Fitbit-Charge-HR physical activity tracker over a 7-week period. Actical accelerometers were used to measure participants' levels of MVPA before and at the end of intervention periods for each group. Covariates such as age, sex, stage of change for physical activity behavior, and goal commitment were also measured.
There was an increase in physical activity over the course of the study period, though it was not related to overall physical activity tracker use. An intervention response did, however, occur in a subset of participants. Specifically, exposure to the physical activity tracker was associated with an average daily increase in MVPA by more than 15 minutes (P=.01) among participants who reported being in the action and maintenance stages of behavior change in relation to participation in physical activity. Participants in the precontemplation, contemplation, and preparation stages of behavior change had no change in their level of MVPA (P=.81).
These results suggest that physical activity trackers may elicit improved physical activity related behavior in young adolescents demonstrating a readiness to be active. Future studies should seek to investigate if integrating physical activity trackers as part of more intensive interventions leads to greater increases in physical activity across different levels of stages of behavior change and if these changes can be sustained over longer periods of time.
只有5%的加拿大青少年达到了每天建议的60分钟中等至剧烈身体活动（MVPA）的标准，休闲时间越来越多地用于使用科技产品。促进身体活动的直接面向消费者的移动健康（mHealth）设备，如腕戴式身体活动追踪器，具有可能吸引青少年的功能。
本研究的主要目的是确定基于极简主义身体活动追踪器的干预措施是否会导致青少年身体活动增加。本研究的次要目的是评估通过追踪器测量的7周干预期间身体活动的变化。
采用准实验交叉设计，将两组23名青少年（13 - 14岁）随机分配到立即干预组或延迟干预组。干预措施包括在7周内佩戴Fitbit Charge HR身体活动追踪器。在每组干预期开始前和结束时，使用Actical加速度计测量参与者的MVPA水平。还测量了年龄、性别、身体活动行为的改变阶段和目标承诺等协变量。
在研究期间，身体活动有所增加，但这与总体使用身体活动追踪器无关。然而，一部分参与者确实出现了干预反应。具体而言，在报告处于与参与身体活动相关的行为改变行动和维持阶段的参与者中，接触身体活动追踪器与MVPA平均每日增加超过15分钟相关（P = 0.01）。处于行为改变前思考、思考和准备阶段的参与者的MVPA水平没有变化（P = 0.81）。
这些结果表明，身体活动追踪器可能会在表现出积极意愿的青少年中引发与身体活动相关行为的改善。未来的研究应寻求调查将身体活动追踪器作为更强化干预措施的一部分是否会导致不同行为改变阶段的身体活动有更大增加，以及这些变化是否能在更长时间内持续。
