Long‐Term, Aerobic Training Increases Adiponectin Levels in Females, but not Males

Abstract

Aerobic training (AT) may increase adiponectin (ADP) levels, but the complex regulation of ADP may be influenced by additional factors such as gender and insulin sensitivity. We first studied the changes in ADP in experienced runners (R; n=12) and beginners (B; n=16) undergoing progressive, long‐term (6 mo) AT. We hypothesized that ADP would increase in both R and B groups, but to different extents. Fasting plasma samples were collected at the beginning and end of the training and analyzed for insulin, glucose, and ADP. ADP increased significantly to similar extents in both R and B groups, but only in females. We studied the effects of insulin sensitivity on ADP levels in a complementary cross‐sectional study using HOMA‐IR scores of <1.8 as insulin‐sensitive (IS) and >2.0 as insulin‐resistant (IR). We hypothesized that ADP levels would be highest among experienced female runners independent of their insulin sensitivity status. Based on the training history, insulin sensitivity, and gender, subjects were separated into 8 different groups. ADP levels in the R‐IS‐F group (n = 10) were significantly higher than those in any other group. Thus, long‐term exercise raises ADP levels in IS females, but not IR females. However, ADP level differences in males appear to be due to insulin sensitivity differences and not long‐term exercise.