Postexercise insulin action in African-American women
Hasson, R.E.; Freedson, P.S.; Braun, B.
Journal of the National Medical Association 98(11): 1832-1839
2006
ISSN/ISBN: 0027-9684 PMID: 17128694 Document Number: 596102
African Americans are more insulin resistant than Caucasians. A single bout of moderate-intensity exercise reduces insulin resistance in sedentary Caucasian individuals. The impact of a single bout of exercise on insulin resistance has never been studied in African Americans. The purpose of this experiment was to evaluate the impact of a single bout of exercise on insulin resistance in African-American women.Design: Insulin resistance was assessed in 10 sedentary, overweight or obese African-American women during a sedentary and exercise condition over a two-day period. During the sedentary condition, participants fasted overnight and sat quietly in the laboratory for 75 minutes. During the exercise condition, participants completed 75 minutes of brisk walking on a treadmill. Ninety minutes following each condition, participants completed an oral glucose tolerance test (OGTT). Three-and-a-half hours later, subjects consumed a standardized meal [meal tolerance test (MTT)].Results: The insulin response to the OGTT was 18% lower (p=0.046), and insulin sensitivity was 18% higher (p=0.042) in the exercise condition compared to the sedentary condition. There were no differences between conditions following the MTT.Conclusions: These results indicate that overweight/obese, sedentary, insulin resistant African-American women had a significant improvement in insulin sensitivity from 75 minutes of brisk walking.