Transfer or Compensation? An experiment testing the effects of actual and imagined exercise on eating.

This study tested the effects of exercise on eating. The transfer hypothesis proposes that exercise leads to generalization of healthy behavior and therefore improved diet. The compensation hypothesis assumes that exercise leads to increased calorie intake to "compensate" for the energy expenditure. We tested these hypotheses both for actual and imagined exercise. Female University members (N=227) were randomized to three experimental groups: actual exercise vs. imagined exercise vs. control. After baseline, participants engaged in a 5-minute experimental task. Thereafter, they were left alone with unhealthy snacks. Participants who imagined themselves exercising (M=101, SD=128 kcal) consumed significantly fewer calories than controls (M=129, SD=142 kcal), consistent with a transfer effect. Participants who engaged in actual exercise but were distracted from thinking about exercise consumed similar quantities (M=127, SD=111 kcal) as controls. This study suggests that transfer effects are underpinned by psychological processes, such as goal activation, which should be investigated in the future.