Department of Psychology, Open University, Heerlen, Netherlands.
Faculty of Science, Prevention and Public Health, Amsterdam Public Health Research Institute, VU University, Amsterdam, Netherlands.
Psychol Health. 2020 Oct;35(10):1184-1206. doi: 10.1080/08870446.2020.1734202. Epub 2020 Mar 5.
To provide insight into the motivational working mechanisms (i.e. mediators) of an effective physical activity (PA) intervention for adults aged over fifty. The mediation model ( = 822) was investigated in an RCT for the total intervention population, participants who were not norm-active at baseline (targeting PA initiation) and norm-active participants (targeting PA maintenance) separately. Potential mediators (attitude, self-efficacy, intention, action planning and coping planning) of the effect on PA (6-months) were assessed at baseline, 3 and/or 6 months. The intervention resulted in a decrease in intention (= -.209; =.017), and an increase in action planning (=.214; =.018) and PA (=.220; =.002). Intention and action planning did not mediate the effect on PA. Self-efficacy, although not significantly influenced by the intervention, was found to be the only motivational variable that predicted change in PA (=.164; =.007). These results were confirmed among participants initiating PA. Among norm-active participants no significant intervention effects were identified. The motivational factors cannot explain the intervention effect on PA. Most likely, the effect can be explained by an interaction between the motivational factors together. Differences between participants initiating versus maintaining PA, highlight the importance of performing mediation analyses per subgroup.
为了深入了解针对 50 岁以上成年人的有效身体活动（PA）干预措施的动机工作机制（即中介因素）。在一项 RCT 中针对总干预人群、基线时非标准活动参与者（针对 PA 起始）和标准活动参与者（针对 PA 维持）分别对中介模型（ = 822）进行了研究。在基线、3 个月和/或 6 个月时评估了对 PA（6 个月）的潜在中介因素（态度、自我效能、意图、行动计划和应对计划）。干预导致意图（ = −.209； =.017）降低，行动计划（ = .214； =.018）和 PA（ = .220； =.002）增加。意图和行动计划并不能解释对 PA 的影响。自我效能虽然没有受到干预的显著影响，但被发现是唯一可以预测 PA 变化的动机变量（ = .164； =.007）。这些结果在开始 PA 的参与者中得到了证实。在标准活动参与者中，没有发现显著的干预效果。动机因素不能解释 PA 干预的效果。很可能，这种效果可以通过动机因素的相互作用来解释。与开始和维持 PA 的参与者之间的差异，突出了按亚组进行中介分析的重要性。
