Combining Short-Term Interval Training with Caloric Restriction Improves ß-Cell Function in Obese Adults

Area of Science:

• Metabolic health
• Endocrinology
• Exercise physiology

Background:

• Low-calorie diets (LCD) are known to improve glucose regulation.
• The additive effect of interval exercise (INT) on glucose metabolism and beta-cell function alongside LCD is not well understood.

Purpose of the Study:

• To investigate the impact of an LCD compared to LCD plus INT on beta-cell function and glucose tolerance in obese adults.
• To assess how these interventions affect insulin secretion and insulin resistance.

Main Methods:

• Twenty-six obese adults were randomized to a 2-week LCD or LCD + INT regimen.
• Oral glucose tolerance tests (OGTT) were conducted, with insulin secretion rates (ISR) analyzed using deconvolution modeling.
• Beta-cell function (Disposition Index) and insulin resistance (Matsuda Index, HOMA-IR) were calculated.

Main Results:

• LCD + INT significantly reduced glucose and insulin secretion rates (ISR) during the OGTT compared to LCD alone.
• Both interventions improved skeletal muscle insulin resistance and enhanced skeletal muscle and hepatic beta-cell function (Disposition Index).
• Improved skeletal muscle beta-cell function was correlated with better glucose tolerance.

Conclusions:

• LCD combined with INT demonstrates superior improvements in glucose tolerance in obese adults compared to LCD alone.
• This combined approach positively impacts beta-cell function, suggesting its potential for type 2 diabetes prevention.
• The findings support LCD + INT as a strategy to preserve pancreatic function.