Effect of physical training on insulin secretion and action in skeletal muscle and adipose tissue of first-degree relatives of type 2 diabetic patients.

Description

The purpose of this study was to investigate the effect of a 12-week endurance training on insulin action in both skeletal muscle and adipose tissue as well as at the whole body level. The study also examined the insulin-secretory capacity in seven first-degree relatives (FDR) of patients with type 2 diabetes and eight control (CON) subjects before and after 12 weeks of endurance training. Results showed that healthy FDR men did not improve their insulin-mediated glucose uptake at the whole body level or in skeletal muscle and adipose tissue in response to physical training, whereas improvements were observed in the CON subjects. However, glucose-mediated glucose uptake increased at the whole body level in both groups. More specifically, the in vivo glucose uptake in subcutaneous abdominal (p<0.05) and femoral (p=0.09) adipose tissue was higher in FDR compared with CON, but it was not affected by training. Glucose-stimulated insulin secretion was lower in FDR than in CON, but neither FDR nor the healthy CON subjects changed their insulin-secretory capacity in response to physical training. Endurance training increased in vivo skeletal muscle lipolysis in both FDR and CON. Thus, these results suggest that insulin-secretory capacity is lower in FDR than in CON and that the impact of endurance training on glucose and insulin homeostasis is different in FDR.