Hormonal and metabolic response to physical exercise in hyperinsulinemic and non-hyperinsulinemic type 2 diabetics

In order to find out the influence of hyperinsulinaemia and initial blood glucose levels on glucose homeostasis during physical exercise, 6 Type 2 diabetic patients with basal hyperinsulinemia (0.209 nmol/l) (group A) and 10 Type 2 diabetics without basal hyperinsulinemia (0.046 nmol/l) (group B) took part in a study on metabolic effects of exercise. Mean bodymass was higher in group A (101 kg) than in group B (71.7 kg). Exercise was performed on a bicycle-ergometer for 1 hr. Work load was adjusted to a pulse-rate of 120/min with a mean of 48 watt (W) in group A and 52 W in group B. Blood glucose (BG), insulin (IRI), glucagon (G), growth hormone (HGH), cortisol (C), epinephrine (E), norepinephrine (NE), lactate (L), pyruvate (P) and free fatty acids (NEFA) were measured during 3 hr. BG and IRI were also documented for the following 7 hr. Both groups showed a small but significant decrease of BG during exercise (group A from 11.54-10.38 mmol/l, p less than 0.01, and group B from 8.71-7.22 mmol/l, p less than 0.005). IRI decreased insignificantly in group A (from 0.209-0.174 nmol/l, p less than 0.15) and significantly in group B (from 0.046-0.032 nmol/l, p less than 0.01). G increased significantly in both groups (from 62.4-75.2 pmol/l in A, p less than 0.05, and from 38.8-47.1 pmol/l in B, p less than 0.01). HGH rose from 0.018-0.149 nmol/l in A, p less than 0.01, and from 0.077-0.320 nmol/l in B, p less than 0.01.(ABSTRACT TRUNCATED AT 250 WORDS)