Exercise versus Nonexercise Activity: E-diaries Unravel Distinct Effects on Mood.

INTRODUCTION: The association between physical activity and mood is of major importance to increase physical activity as a prevention strategy for noncommunicable diseases and to improve mental health. Unfortunately, existing studies examining how physical activity and mood wax and wane within persons over time in everyday life do show ambiguous findings. Taking a closer look at these studies reveals that the aggregation levels differ tremendously. Whereas mood is conceptualized as a three-dimensional construct, physical activity is treated as a global construct not taking into account its distinct components like exercise (such as jogging) and nonexercise activity (NEA; such as climbing stairs).

METHODS: To overcome these limitations, we conducted an ambulatory assessment study on the everyday life of 106 adults over 7 d continuously measuring NEA via accelerometers and repeatedly querying for mood in real time via GPS-triggered e-diaries. We used multilevel modeling to derive differential within-subject effects of exercise versus NEA on mood and to conduct analyses on the temporal course of effects.

RESULTS: Analyses revealed that exercise increased valence (beta = 0.023; P < 0.05) and calmness (beta = 0.022; P < 0.05). A tendency of decreasing energetic arousal (beta = -0.029) lacked significance. NEA, parameterized as 15-min episodes of physical activity intensity in everyday life, increased energetic arousal (beta = 0.135; P < 0.001) and decreased calmness (stand. beta = -0.080; P < 0.001). A tendency of increasing valence (beta = 0.014) lacked significance. Using longer time intervals for NEA revealed similar findings, thus confirming our findings.

CONCLUSION: Exercise and NEA differed regarding their within-subject effects on mood, whereas exercise increased valence and calmness, NEA increased energetic arousal and decreased calmness. Therefore, it appears necessary to clearly differentiate between exercise and NEA regarding their within-subject effects on mood dimensions in both research and treatment.