Substituting food restriction by resistance training prevents liver and body fat regain in ovariectomized rats

Abstract

Objective Fat mass gain and regain following weight loss are major concerns and may be even more critical after menopause. The present study was undertaken to evaluate the effect of a resistance training protocol on body weight and fat mass in ovariectomized Sprague–Dawley rats following diet-induced weight loss.

Design Rats were randomly divided into ovariectomized (Ovx) and sham-operated (Sham) groups. Five weeks after ovariectomy, Ovx rats were subjected to a 26% food restriction (OvxFR) for 8 weeks. Following this period, OvxFR rats went back to a normal ad libitum feeding and were divided into two groups: either sedentary or undergoing a resistance training program for an additional 5 weeks, which consisted of climbing a 6-m vertical grill, 20–40 times, with progressively increasing load four times/week.

Results The food restriction program decreased (p < 0.01) body mass, fat pad weight (intra-abdominal and subcutaneous), and liver triacylglycerol (TAG) levels as compared to normally fed Ovx rats. Stopping the food restriction program over a 5-week period resulted in a partial regain in body weight and intra-abdominal fat pad weight (p < 0.05), and in an almost complete regain in liver TAG compared to normally fed Ovx rats. On the other hand, no significant increases in these variables were noted when the food restriction was replaced by resistance training over the same 5-week period.

Conclusion These results indicate that a resistance training program could be useful in preventing body weight as well as adipose tissue and liver fat regain in Ovx rats, following diet-induced weight loss. It is suggested that changing from a food restriction regimen to a resistance training program can be an interesting strategy to promote successful long-term weight reduction in postmenopausal women.

Key words:

• Body Mass
• Food Restriction
• Exercise
• Hepatic Steatosis
• Plasma Lipids
• Menopause