A Daily Diary of the Quantified Self – The Influence of Fitness App Usage on Psychological Well-Being, Body Listening and Body Trusting

Continuous self-tracking via fitness apps has become popular and has been described as a way of practicing body awareness. Many app providers have implemented a daily step target option in the app. However, potential effects of fitness app usage and specific app functions (i.e., a step target of 10,000 steps per day) on psychological well-being and aspects of body awareness are still unclear. It was the aim of this study to examine these effects and to explore causal relationships between body trusting and well-being.Novice fitness app users (Age: M = 24.66 years ranging from 18–40 years) were recruited. Two randomized groups (each n = 50) used a fitness tracker device for six weeks. One group was provided with a pre-defined target of 10,000 steps per day, whereas the second group was not. A third control group (n = 52) documented their daily physical activity. A daily diary method was used to measure well-being, body listening and body trusting. In Bayesian multilevel analyses, we found neither time nor group-time interaction effects. These results were robust when controlling for a range of variables (e.g., physical activity, age). Longitudinal connections between body trusting and well-being were observed, however varying when controlling for auto-correlation. We concluded that exercise-related self-tracking via fitness app usage and specific external step goals does not substantially influence psychological well-being, body trusting and body listening. Considering the large variability in effects, potential positive effects can be assumed under specific conditions that are to be identified in further studies.