Effect of resistance training with or without chromium picolinate supplementation on glucose metabolism in older men and women

The effect of 12 weeks of resistance training (RT) with or without chromium picolinate (Cr-pic) supplementation on glucose tolerance was assessed in m oderately overweight older men and women (age, 62 +/- 4 years; body mass in dex [BMI], 29.1 +/- 2.5 kg/m(2)). Seventeen men and 15 women were randomize d to groups that consumed either 17.8 mu mol chromium per day (924 mu g Cr/ d) as Cr-pic or a placebo (<0.1 mu g Cr/d) while performing RT twice weekly . For all 32 subjects combined, fasting glucose increased but there were no changes in insulin or C-peptide concentrations after 12 weeks of Ri, In re sponse to an oral glucose challenge, the glucose and C-peptide areas under the curve (AUCs) were unchanged, whereas there was a 19% decrease in the in sulin AUC (from 68 +/- 53 to 55 +/- 29 x 10(3) pmol/L/180 min, P = .045). T he RT responses for the fasting concentration or AUC for glucose, insulin, or C-peptide were not influenced by Cr-pic. The decrease in the insulin AUC without any change in insulin secretion, as evidenced by a lack of change in the C-peptide AUG, suggests enhanced insulin clearance from the circulat ion with RT. Collectively, these data suggest that RT decreases the insulin response following an oral glucose challenge in older moderately overweigh t men and women without affecting glucose tolerance. The data also suggest that the decrease in circulating insulin may result from an increase in ins ulin clearance, not a decrease in insulin secretion. High-dose Cr-pic suppl ementation had no effect on any measure of glucose metabolism during RT. Co pyright (C) 1999 by W.B. Saunders Company.