Cognitive Effects of Adding Caloric Restriction to Aerobic Exercise Training in Older Adults with Obesity.

OBJECTIVE

This study examined the short- and long-term effects of adding caloric restriction to 5 months of aerobic exercise training on executive function in sedentary older adults with obesity.

METHODS

Sedentary adults with obesity aged 65 to 79 years completed a randomized trial investigating the cardiorespiratory benefits of adding moderate (~ 250 kcal) or high (~ 600 kcal) caloric restriction to a 20-week aerobic exercise program. Approximately half (n = 88) completed a cognitive assessment battery at baseline, post intervention, and 18 to 24 months after intervention completion. The primary outcome was an executive function composite score.

RESULTS

In the overall sample, the executive function composite increased 0.114 from baseline to postintervention (P = 0.01). Randomization to caloric restriction did not significantly alter executive function over aerobic exercise alone, nor were there between-group differences on any individual executive function test following the intervention or at long-term follow-up. Adding caloric restriction to exercise was associated with a modest increase in Mini-Mental State Examination score (P = 0.04). In the overall sample, increases from baseline at long-term follow-up were noted in digit symbol and word list recall performance as well.

CONCLUSIONS

Adding caloric restriction to a 20-week aerobic exercise program does not worsen or improve executive function more than exercise alone assessed up to 24 months post randomization.