A Quasi-Experimental Study of a Fitbit-Based Self-Regulation Intervention to Improve Physical Activity, Well-Being, and Mental Health.

Self-regulation strategies are helpful for increasing goal commitment and maintaining behavior change. Evidence suggests that the self-regulation strategy of mental contrasting with implementation intentions (MCII) shows promise in helping people increase their physical activity. The purpose of this research was to investigate whether these self-regulation strategies would increase physical activity, which would, in turn, improve well-being and mental health. In a quasi-experimental study, participants were randomized by school to an experimental group (n = 40) and control group (n = 45). The experimental group received self-regulation strategies, whereas the control group did not. Both groups were given a Fitbit and the goal of 10,000 steps per day. Participants' well-being and depressive, anxiety, and stress symptoms were measured at baseline and after the 3-week intervention. The experimental group's physical activity increased from 7,938 to 9,288 steps per day (p = 0.001), whereas that of the control group did not increase. In the experimental group, the findings suggested a significant increase for men, and a nonsignificant increasing trend for women. The study demonstrated the benefits of self-regulation strategies such as MCII on achieving physical activity goals. Findings also suggested that self-regulation strategies provided improvement beyond physical activity by decreasing the depressive symptoms of female participants in the experimental group. Given the small sample size, effects by gender have to be interpreted with caution. Limitations and suggestions for future research are discussed.