COVID-19 Pandemic and Exercise (COPE) Trial: Engagement with exercise apps and psychological stress

Engaging in physical activity can reduce the risk of multiple morbidities and premature mortality. Psychological stress can hinder the development and maintenance of physical activity behaviors. There is a dearth of research on how these two processes interact. The purpose of this study was to identify the week-to-week bidirectional associations between psychological stress and adherence to a six-week mHealth exercise program among a previously inactive sample. The secondary analyses reported in this study examine data derived from adults randomized to one of three mobile application(s)-based exercise arms embedded within the COVID-19 Pandemic and Exercise(COPE) Trial (N = 251). The interventions delivered to participants in each arm involved six weeks of at-home exercise requiring no additional equipment. Relationships between psychological stress and engagement with the commercially available exercise apps were explored using a random intercept cross-lagged panel model. This model simultaneously assessed the longitudinal and bidirectional associations between psychological stress and subsequent exercise adherence and vice versa. Both psychological stress and engagement with the exercise interventions demonstrated significant positive autoregressive effects across successive weeks. However, the cross-lagged associations between psychological stress and engagement with the exercise intervention were not significant. While the cross-lagged effects were non-significant, there was high variability between individuals. Future studies should use larger samples and methods that would allow an examination of an individual's relationship between stress and exercise engagement.