[Effects of different intensity interval exercise of 6 weeks on body composition of obese rats]

Abstract

Objective: To investigate the effects of different intensity intermittent exercise on the body function of obese rats, and to provide basis for the prevention and treatment of obesity.

Methods: Eighty SD rats were randomly divided into normal diet group (n=20) and high-fat diet group (n=60). After adaptive feeding for 8 weeks, 8 normal diet rats and 32 high-fat obese rats were selected for follow-up experiments. The experimental rats were randomly divided into 5 groups (n=8): control diet-sedentary (CS),with ordinary feed and without any exercise; high diet-sedentary (HS), with high-fat feed feeding and without any exercise; high diet-continual exercise(HC), 60 min/day,5 days/week with 6 weeks; high diet-long time-low frequency interval exercise(HLL), 30 min/time,twice/day (intermittent 6 h), 5 days/week with 6 weeks; high diet-short time-high frequency interval exercise(HSH), 20 min/ time, 3 times/d (intermittent 3 h), 5 days/week with 6 weeks. The training intensity of rats in each exercise group was 25 m/min. After 6 weeks, rats in each groups were weighed, and resting metabolic rate(RMR), fasting blood glucose(FBG), triglyceride(TG) and other biochemical indexes were detected, and fat and muscle weight were measured.

Results: Before experiment, there were no significant differences in RMR, FBG and TG in each groups(P＞0.05).The body weight of HSH, HLL, HC and HS groups was higher than that of CS group (P＜0.05). After the experiment, RMR of the HSH,HLL and HC groups was significantly higher than that of HS and CS groups (P＜0.05), but without significant difference among the HSH,HLL and HC groups (P＞0.05).The body weight of HSH, HLL and HC groups was significantly lower than that of HS group (P＜0.05), but the three groups was not significant (P＞0.05); perirenal fat(PF), idymis fat(EF), perirenal fat/weight(PF/W) and epididymis fat/weight(EF/W) of HSH, HLL, HC group were significantly lower than those of HS group (P＜0.01), while there was no statistical difference among the three groups (P＞0.05). There was no significant difference in gastrocnemius(GM) and quadricep(QF) of each group (P＞0.05), gastrocnemius/weight(GM/W) and quadriceps/weight (QF/W) in HSH,HLL and HC groups were higher than those of HS group (P＜0.05),while there was no significant difference among HSH,HLL and HC groups (P＞0.05);FEB,TG of HSH,HLL,HC group were lower than those of CS and HS group (P＜0.05),but the difference with HS group was more significant (P＜0.01),there was no significant difference among training groups(P＞0.05).

Conclusion: 6 weeks of intermittent exercise of different intensity had a good intervention effect on the body composition of obese rats, and high diet-short time-high frequency interval exercise (HSH) may be more effective.