Abstract
Although it is well known that exercise reduces depressive symptoms,the underlying psychological mechanisms remain unclear.This experimental study examined the acute effect of exercise onmood, and depressotypic memory bias and state rumination. Traitrumination was tested as a possible moderator. A sample of nonregularexercisers (N = 100) was randomized to exercise or rest.After a negative mood induction, the exercise condition cycled for24 min at moderate intensity, while the rest condition rested.Negative and overgeneral memory bias, as well as positive andnegative affect were assessed after exercise/rest. To capture thelingering of negative mood and state rumination, both wereassessed multiple times throughout the study. The exercise (ascompared to rest) condition reported more positive affect.However, no differences were found on overgeneral memory bias,as well as depression-specific mood or state rumination measuredthroughout the study. Interestingly, the exercise condition showedmore negative memory bias at higher levels of rumination.Individual differences in trait rumination moderated the exercise—memory bias relation, such that exercise increased negativememory bias at higher levels of rumination. It is possible that longtermexercise protocols are necessary to change cognitive processesrelated to depression.
