Exercise and dietary program-induced weight reduction is associated with cognitive function among obese adolescents: a longitudinal study

OBJECTIVE: The present study was to determine the effect of a combined exercise and dietary program on cognitive function as well as the relationship between the program-induced weight change and cognitive function alterations. DESIGN: The study applies a quasi-experimental design. METHODS: Fifty-eight adolescents with obese status (body mass index, BMI >28 kg/m(2)) were assigned to either an experiment (n = 30) or control group (n = 28). Participants in the experiment group received a scheduled program with a specific exercise protocol (two sessions per day, six days per week) and diet plan for four consecutive weeks; the control group was instructed to maintain their normal school activities. The primary outcome measures were anthropometric data and flanker task performance. RESULTS: The combined program led to reduced BMI with maintenance of the incongruent accuracy in the experiment group, but the incongruent accuracy decreased in the control group after the four-week period. Additionally, the change in weight status between post- and pre-test measurements was inversely correlated with the change in incongruent accuracy. CONCLUSION: The combined exercise and dietary program resulted in decreased weight and enhanced executive function in the obese adolescents, and the weight alteration may be considered the mediator between the intervention and executive function.