The Effect of 12 Weeks of High Intensity Functional Training (HIFT) on Serum Mitokine and Metabolic Risk Factors in Patients with Metabolic Syndrome: A Randomized Control Trial

Background Metabolic syndrome is a disease related to mitochondrial dysfunction. Mitokines such as FGF21 and GDF15, recognized as biomarkers associated with metabolic stress, play crucial roles in regulating energy and inflammation. This study aimed to investigate the effects of High-Intensity Functional Training (HIFT) on the serum levels of FGF21 and GDF15, metabolic risk factors and body composition in middle-aged men with metabolic syndrome. Methods In a randomized controlled trial, 24 men (age = 42.40 ± 6.90 years) with metabolic syndrome were randomly assigned to either the HIFT group or the control group. The HIFT group performed exercise sessions twice a week for 12 weeks, and each session lasted 50–60 minutes. Anthropometric and biochemical assessments were conducted before and after the intervention. Results After the intervention, the FGF21 and GDF15 levels significantly decreased in the HIFT group (P = 0.001). Furthermore, body fat percentage, fasting blood glucose, HbA1c, blood lipids, and LDL-C decreased, whereas skeletal muscle mass and HDL increased (P < 0.001, for all). Conclusion HIFT improved metabolic health by modulating the serum levels of mitokines, metabolic risk factors and body composition. Therefore, this type of training can be recommended as an effective nonpharmacological intervention for prevention and treatment of patients with metabolic syndrome. Trial registry Iranian Registry of Clinical Trials identifier: IRCT20241130063899N1, prospectively registered 10-11- 2025, https://irct.behdasht.gov.ir/trial/80642