Effect of Exercise Training on Serum FGF21 Level in Adults with Metabolic Disorders, A Meta-Analysis

Background and objective: Effects of exercise training on metabolic disorders through modifications in fibroblast growth factor -21 (FGF-21) level are controversial. Therefore, the aim of study was to determine the quantitative effect of exercise training protocols on serum FGF-21 level in adults with metabolic disorders. Methods: A systematic search of the published Persian or English-language studies from PubMed and Google Scholar databases up to march 2021 was done and standardized mean differences (SMDs) were calculated using random-effects models. Results: a total of 14 studies (aerobic training=3, resistance training=3, HIIT=4, concurrent training=4) including on 19 interventions conducted on 503 subjects (with overweight, obesity, type 2 diabetes, metabolic syndrome and or fatty liver disease) were eligible to include in the meta-analysis. However, because of the heterogeneity, the final quantitative impact of 16 interventions was calculated as a declining serum FGF21 level after training [SMD=-0.44(CI: -0.65 to -0.22) p=0.001] which had no correlation with subjects age(p=0.10) or BMI(p=0.50) level. Conclusion: exercise training protocols are efficient tools for a remarkable decrease in serum FGF-21 in patients with metabolic disorders which seems to lead to more beneficial effects on metabolic disturbances. However, more clinical trials are still warranted in this area considering the role of exercise components such as exercise intensity and type