Exercise in a behavioural weight control programme for obese patients with type 2 (non-insulin-dependent) diabetes

Two studies were conducted to determine whether adding exercise to a diet programme promotes weight loss or glycaemic control in Type 2 (non-insulin-dependent) diabetic subjects. In Study 1, 25 subjects were randomly assigned to diet plus moderate exercise or diet plus placebo exercise. All subjects exercised twice a week as a group and once a week on their own; the diet plus moderate exercise group walked a 3-mile route at each session while the diet plus placebo exercise group did very low intensity exercises such as stretching and light calisthenics. All subjects followed a calorie-counting diet and were taught behaviour modification strategies. Weight losses and improvements in glycaemic control did not differ significantly between the two treatment groups at the end of the 10-week treatment or at 1-year follow-up. In Study 2, more extreme conditions were compared: a diet only group and a diet plus exercise group. The diet plus exercise group walked a 3-mile route with the group 3 times/week and once a week on their own, while the diet only group was instructed to maintain their current low level of activity. Both groups received comparable diet and behaviour modification instruction and therapist contacts. The diet plus exercise group had significantly (p less than 0.01) better weight losses than the diet only condition at the end of the 10 week programme (-9.3 kg vs -5.6 kg) and at 1 year follow-up (-7.9 kg vs -3.8 kg).