Objective:

To investigate the effects of a training program based on aerobic interval exercise combined with resistance training and caloric restriction, on final body weight and body composition of genetically obese rats.

Methods:

Thirty-two genetically obese rats were randomly divided into two groups (n = 16) with or without aerobic interval exercise combined with resistance training. In turn, each group, with or without aerobic interval exercise combined with resistance training, was divided into two groups, with or without caloric restriction, resulting 4 intervention groups (n = 8). The training groups conducted an aerobic interval exercise combined with resistance training program in a 60 min session, five days/week for two months. Calorie-resticted groups consumed 30% less food than ad libitum groups. Body weight and carcass was determined with a precision balance and fat, muscle mass and body water was assessed using a body composition analyzer based in nuclear magnetic resonance, especially designed for rats.

Results:

Final body weight was lower in animals that followed the caloric restriction compared to those fed ad libitum (P < .001). Fat mass was lower and muscle mass higher in those animals that developed aerobic interval exercise combined with resistance training compared to the sedentary groups (P < .001) without differences attending to the caloric restriction (all P > .05). Interactions of caloric restriction versus training were observed on muscular mass and total body water. The highest value of muscle mass and body water was observed in those animals that combined the training protocol with the caloric restriction (both, P < .01).

Conclusion:

Both, the aerobic interval exercise program combined with resistance training program developed and caloric restriction enhanced body composition in obese rats, but exercise improved it further.