Brisk walking reduces ad libitum snacking in regular chocolate eaters during a workplace simulation

Workplace snacking can contribute to obesity. Exercise reduces chocolate cravings but effects on chocolate consumption are unknown. This study investigated the effect of brief exercise on ad libitum consumption during breaks in a computerised task. Seventy-eight regular chocolate eaters, age: 24.90 ± 8.15 years, BMI: 23.56 ± 3.78 kg/m2 abstained for 2 days. They were randomly assigned to one of four conditions, in a 2 × 2 factorial design, involving either a 15 min brisk walk or quiet rest, and then computerised Stroop tasks with low or high demanding conditions, in three 180 s blocks with a 90 s interval. Throughout, a pre-weighed bowl of chocolates was available for ad libitum eating. A two-way ANOVA revealed no interaction effect of exercise and stress on total chocolate consumption, or main effect of stress, but a main effect of exercise [F(1, 74) = 7.12, p < .01]. Mean (SD) chocolate consumption was less (t(73.5) = 2.69, 95% CI for difference 3.4–22.9, ES = 0.61) for the exercise (15.6 g) than control (28.8 g) group. Exercise also increased affective activation, but there was no mediating effect of change in affect on chocolate consumption. A brief walk may help to reduce ad libitum snacking in regular chocolate eaters.

► Exercise almost halved ad libitum chocolate consumption among regular chocolate eaters, while performing a computerised task.
► The level of task demand had little influence on the results.
► Exercise also increased level of affective activation.
► Changes in affective activation did not mediate the effects of exercise on chocolate consumption.