Effect of high fat diet on endurance capacity and oxydative enzyme activities in rat skeletal muscle.

2000 Fiscal Year Final Research Report Summary

• Project/Area Number: 10680029
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 体育学
• Research Institution: Nara University of Education
• Principal Investigator: NAKATANI Akira Nara University of Education, Education, Professor, 教育学部, 教授 (70116284)
• Project Period (FY): 1998 – 2000
• Keywords: rat / high-fat diet / glycogen / oxydative enzyme activity / endurance capacity

Research Abstract

The purpose of this study was to determine the effect of high fat diet on endurance capacity and oxidative enzyme activities in rat skeletal muscle.
Male Wistar rats were assigned to either a high fat diet and a low fat diet group. They ate these diets ad libitum for 5 weeks. Although triceps muscle glycogen concentration in the high fat diet group was about half of that in the low fat diet group, swimming capacity was significantly higher in the high fat than in the low fat diet group. The high fat diet induced significant increases in citrate synthase (CS) and 3-hydroxyacyl CoA dehydrogenase (3-HAD) activities in triceps muscle (23% and 47%, respectively).
Wistar rats were fed one of four diets : low fat (12% calories as fat) , lard (60% calories as fat) , safflower oil (60% calories as fat) , or fish oil (60% calories as fat). There were no significant differences in body weight among each diet group. Epidydimal adipose tissue weight was higher in lard and safflower oil groups than in low fat. Safflower and fish oil diet induced significant increases in CS and 3-HAD activities in red portion of gastrocnemius muscle.
These results suggest that long term feeding of a high fat diet increases mitochondrial enzyme activities in skeletal muscle, and these increases might induce glycogen sparing and thus improve endurance.