Document Type : Research Paper
PhD Student of Exercise Physiology, Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, University of Guilan, Iran
Professor, Department of Exercise Physiology, Faculty of Physical Education and Sport Sciences, University of Guilan, Iran
Insulin resistance induced by a high fat diet has been associated with intramuscular lipid metabolites. The aim of this study was to investigate the effect of aerobic exercise, diet restriction and their combination on insulin resistance through intramuscular diacylglycerol changes in obese male rats. Sample consisted of 56 male Wistar rats (mean weight: 194.5±12.6 g). 48 rats had a high-fat diet for 18 weeks and 8 rats had normal diet. Then, high-fat diet rats were divided into control (C), aerobic Exercise (E), caloric restriction (CR), and a combination (aerobic Exercise + caloric restriction (E+C) groups. E group ran on a treadmill at 28 m. per minute for 10 weeks. In CR group, 25% of their daily caloric ingestion reduced and E+C group had aerobic exercise and caloric restriction every other day. The results indicated that rats gained weight after 18 weeks of high-fat diet (P<0.05). Also, there was a significant difference in muscle DAG and serum levels of insulin, glucose and insulin resistance index between aerobic exercise, calorie restriction and combination groups and high-fat group (P<0.05). PKC-θ levels decreased in negative energy balance groups (P>0.05). Also, there was a significant difference between E and E+C groups and high-fat diet group in GLUT4 levels (P>0.05). This study indicated that negative energy balance methods can decrease skeletal muscle DAG even along with a high-fat diet which is largely congruent with an improvement in insulin resistance.