Objective: To assess the effects of 1 and 7 consecutive days of exercise on glucose and insulin responses to an oral glucose challenge.
Design: Intervention group assessed at baseline and after 1 and 7 days of exercise.
Setting: Academic medical institution.
Participants: Nine healthy 60 to 80-year-old men and women.
Intervention: Seven days of 50 minutes of exercise at 70% VO2 max.
Measurements: Body weight, body composition, and glucose and insulin levels and responses to an oral glucose challenge at baseline and after 1 and 7 days of exercise.
Main results: Fasting plasma insulin levels and plasma insulin responses to an oral glucose challenge were reduced by 15% and 20%, respectively, with 7 consecutive days of exercise that resulted in no change in body weight or body composition. No changes in glucose or insulin levels or responses to the oral glucose challenge were evident after a single day of exercise.
Conclusion: The hyperinsulinemia associated with aging can be blunted significantly by repeated bouts of exercise in the elderly, independent of any changes in body composition.