Comparing the benefits of different exercise programs for patients with prediabetes

This study examined the effect of exercise at various intensities in reducing glucose levels in patients with prediabetes. Researchers reported the greatest overall improvements for patients undergoing a diet, exercise, and weight loss program. Exercise alone at moderate intensity done a high amount of times per week was nearly as effective.

Patients with elevated blood glucose (sugar) levels that are not quite at diabetic levels are said to have prediabetes. These patients often have decreased sensitivity to the hormone insulin, which is needed to break down the glucose taken in from food. Impaired fasting glucose is also commonly seen in prediabetes. This refers to glucose levels that are higher than normal after a period without food or drink. Impaired glucose tolerance refers to glucose levels that are higher than normal for a long period after glucose intake from food.

Lifestyle interventions can help slow or prevent the progression from prediabetes to type 2 diabetes. These interventions usually involve diet, exercise, and weight loss. Whether exercise alone is effective at reducing glucose levels in patients with prediabetes has not been fully studied.

The aim of this study was to examine the benefit of exercise at various intensities in reducing glucose levels in patients with prediabetes.

237 patients were included in this study. All patients showed signs of prediabetes, based on two blood glucose tests carried out at the beginning of the study. None of the patients were physically active before the study. Patients were randomly assigned to one of 4 intervention groups, each lasting 6 months. In 3 groups, exercise intensity was either moderate or vigorous, done either a high or low amount of times per week. The 4th group was assigned to do a low amount of weekly exercise at moderate intensity plus a diet to reduce body weight by 7% over 7 months.

All interventions improved insulin sensitivity. However, only the diet and exercise group showed a significant decrease in fasting blood glucose levels.

The diet and exercise group also showed the greatest improvement in glucose tolerance (8.2% compared to baseline). Patients doing a high amount of moderate-intensity exercise per week also showed a significant improvement in glucose tolerance (6.4%). Overall, they achieved 79% of the improvement observed in the diet and exercise group. Their improvement in glucose tolerance was also significantly greater compared to the high amount/vigorous-intensity group (1.2%). The low amount/moderate-intensity group was intermediate between these two.

Researchers concluded that a high amount of moderate-intensity per week over 6 months was nearly as effective as a diet and exercise program in improving glucose tolerance. Diet, exercise, and weight loss was associated with the greatest improvements overall.