Glucose tolerance is improved after low- and high-intensity exercise in middle-age men and women

We compared the effects of low- and high-intensity exercise on oral glucose tolerance immediately and 24 hr after each exercise bout. Participants were 5 male and 5 female individuals (age 40-48). A fasted, oral glucose tolerance test (OGTT) was conducted several days before the first exercise bout. Glucose and insulin concentrations were determined every 15 min throughout a 2 hr, 75 g OGTT. Immediately after low-intensity exercise, the incremental glucose area under the curve was reduced by 16%, compared to the fasting OGTT (p < .05). This was reduced further (-30%) 24 hr postexercise (p < .05). After high-intensity exercise, similar results were observed, with the incremental glucose area reduced by 14 and 35% immediately and 24 hr postexercise, respectively (p < .05). In conclusion, exercise improves glucose tolerance, this effect is more pronounced 24 hr postexercise, and low- and high-intensity exercise provide similar beneficial effects on glucose tolerance.