The effect of an excercise intervention on mood is mediated by eating attitude change

Physical exercise is associated with improved mood and psychological wellbeing, but the underlying mechanisms remain unclear. We assessed the relative importance of change in exercise, weight-loss and psychological variables (social support, self-esteem, self-efficacy, disordered eating attitudes and body image) in predicting changes in mood following an exercise intervention; and tested the mediating role of disordered eating attitudes in the relationship between exercise intervention and mood improvement. Adult women enrolled in a 12 week exercise intervention (GFC group) (N=17 ) or a control group (N=40) were assessed for key exercise, weight, mood and psychological wellbeing variables at four time points across a 16 week period. Significant positive mood and psychological wellbeing changes were observed in the GFC group but not the control group following the 12 week exercise intervention. Regression analysis revealed decrease in disordered eating attitudes to be the most consistent and significant predictor of positive mood change associated with exercise intervention. Mediation analysis revealed that disordered eating attitude change was a significant mediator of mood improvements observed following the exercise intervention. This study provides preliminary evidence to suggest an important role of disordered eating attitudes in understanding exercise-related mood improvements and supports models that highlight the importance of psychological aspects to exercise interventions.