Studies indicate that rapid weight gain at critical development stages, such as the lactation period, is associated with the development of obesity, cardiovascular diseases, and diabetes in the long term. In addition to metabolic changes during adulthood, overweight/obesity may influence reproductive function. Human and animal studies suggest that lifestyle changes through exercise and/or controlled diet result in improved semen quality in obese individuals. However, the relationship between exercise volume/intensity and reproductive capacity effects remains inconclusive. The present study aimed to evaluate the effects of moderate intensity endurance training and high-intensity interval training (HIIT) on the reproductive parameters of lactating overfed male Wistar rats. Postnatal overfeeding was induced by applying the litter size reduction method. Forty males Wistar rats were used, divided into four groups: one with control litters (CLs) (10 animals/litter-sedentary) and three with small litters (SLs) (4 animals/litter), divided into sedentary, moderate endurance training, and HIIT. Morphologic, metabolic, and reproductive variables were analyzed. SL sedentary group showed increased body weight, adiposity, and decreased relative weight of the seminal vesicle, prostate, and epididymis as well as changes in the insulin tolerance and oral glucose tolerance tests glycemic tests compared to CL sedentary group. Endurance and HIIT protocols were efficient in improving the glycemic metabolism, central fat accumulation of trained groups and did not affect reproductive parameters. Endurance and HIIT protocols proved to be effective in reversing these metabolic changes without impairing the evaluated reproductive parameters.
Keywords: Aerobic exercise; high-intensity interval training; male infertility; obesity; seminal profile; sperm count.