Skeletal muscle metabolomics analysis after high-intensity interval training in rats fed a high-fat diet

High-fat diet (HFD) causes disturbances in energy production pathways and increases the possibility of insulin resistance (IR). The purpose of this study was to investigate the effect of high-intensity interval training (HIIT) on metabolic profile associated with IR in male rats fed with HFD and standard diet (SD).

32 male rats (aged 7-8 weeks) were divided into four equal groups including HIIT+HFD, HIIT+SD, HFD control, and SD control. Then, HIIT (12 weeks, five sessions per week at intensity of 85-90% of maximum oxygen consumption) and diet interventions were applied and finally, the gastrocnemius muscle was removed for tissue examination by gas chromatography-mass spectrometry. One-way analysis of variance, one-way analysis of covariance, and Kruskal-Wallis tests were used for data analysis at a significance level of P < 0.05.

The level of citric acid in the gastrocnemius muscle was significantly lower in the HFD control group than in the SD control group. In addition, the level of citric acid in HIIT+SD and HIIT+HFD groups was significantly higher than in the HFD control group. There was no significant difference between the levels of malate, glucose 6-phosphate, ribose, xylose, and ribulose 5-phosphate metabolites among the groups. Also, the body weight in the HIIT+SD and HIIT+HFD groups was significantly lower than the HFD control group.

HFD limits the aerobic energy provision of skeletal muscles by reducing the level of muscle citric acid as an important intermediate metabolite in the TCA cycle. HIIT can be effectively reduced metabolic disorders caused by HFD by increasing the level of citric acid and reducing the slope of body weight gain.