THE EFFECTS OF HIGH INTENSITY INTERVAL TRAINING ON SERUM LEVELS OF FGF21 AND INSULIN RESISTANCE IN OBESE MEN

Fibroblast growth factor 21 (FGF21) plays an important role in regulation of energy metabolism and insulin resistance; however, the synergistic effects of high intensity interval training (HIIT) on FGF21 and insulin resistance are not elucidated which was focused in this study. This experimental research was conducted by pretest- posttest design with control group. In this study, 24 obese men were assigned into two groups including
HIIT (n=12, age: 39.83 ± 5.63 years, weight: 100.83 ± 5.81 kg and body mass index: 32.73 ± 2.8 kg/m2) and Control (n=12, age: 39.41 ± 5.23 years, weight: 100.08 ± 4.71 kg, and body mass index: 32.34 ± 1.43 kg/m2). The HIIT group experienced eight weeks of intensive exercises (three sessions per week, four bouts in each session at the intensity of 85-90% of maximum heart rate (MHR) with 3-minute active rest intervals (at 60-50% of MHR) between exercise bouts. Blood samples were collected at baseline and also 48 hours following to the last training session. The data were compared using paired and independent samples t tests. HIIT resulted in a contemporary reduction of plasma glucose and serum insulin and FGF21 and also improved HOMA index (P˂0/05). High intensity interval training plays an effective role in improvement of insulin resistance and reduction of serum FGF21 in obese subjects, which may be due to an improved FGF21 resistance.