The effects of exercise on mood changes: the moderating effect of depressed mood

Background. The present study examined the extent to which pre-exercise depressed mood moderated the influence of exercise on changes in other mood dimensions. The study was conducted in an ecologically valid setting using participants with previous experience of aerobic dance exercise. We hypothesized that (a) exercise will be associated with improved mood regardless of depressed mood, (b) the effect of exercise on mood changes would be significantly greater among individuals that reported symptoms of depressed mood before exercise, and (c) that pre-exercise depressed mood will be associated with a mood profile comprising high anger, confusion, fatigue, and tension, with low vigor. Methods. Participants were 80 (M=27.90 years, SD=4.32 years) exercisers who had attended an exercise class on a regular basis for the previous three months. Participants completed the Profile of Mood States-A 15 minutes before exercise and then immediately after an aerobic dance exercise class. To examine the proposed moderating influence of depressed mood, participants were grouped into either a no-depression group, or a depressed mood group using pre-exercise depression scores. The exercise intervention was an aerobic dance session where participants followed the moves of the instructor. The session lasted for 60 minutes including a warm-up, main session, and cool-down. Results. Repeated measures MANOVA (time x depression/no-depression group) results indicated that anger, confusion, fatigue, tension, and vigor reduced significantly. Thus supporting the notion that exercise reduces negative mood. Results indicated that the reduction in anger, confusion, fatigue, and tension, and increase in vigor was significantly greater in the depressed mood group, hence consistent with theoretical predictions. Results demonstrated that pre-exercise depressed mood was associated with a negative mood profile as hypothesized. Conclusions. Findings lend support to the notion that exercise is associated with improved mood. However, findings show that this effect was significantly greater among individuals reporting symptoms of depressed mood before exercise.