High-intensity functional training modulates oxidative stress and improves physical performance in adolescent male soccer players: A randomized controlled trial

Abstract Regular exercise training can decrease oxidative stress (OS) and up-regulate antioxidant functions in adult population. However, limited data exists considering OS responses in the pediatric population. The aim of this study was to investigate the effect of high-intensity functional training (HIFT) on the OS and performance in adolescent soccer players. In this randomized controlled trial, 20 adolescent soccer players (male, well-trained) were randomly divided into high intensity functional training (HIFT, n=10) and moderate intensity soccer technical training (MITT, n=10) groups. HIFT and MITT was performed for 8 weeks (3 days/week). Baseline OS biomarkers (MDA, 8-OHDG, H 2 O 2 , GPx and CAT) and physical performance (VO 2peak , vertical jump height (VJH) and maximal explosive power (MEP)) were assessed before and after the intervention. Repeated measure mixed ANOVA (2×2) with a significance level of P<0.05 was used to determine differences between and within subjects. The main effect of interaction was significant for VO 2peak , VJH and MEP (P<0.05). The main effect of interaction was not significant for CAT, 8-OHDG, GPx, H 2 O 2 and MDA (P>0.05). Following intervention, VO 2peak and VJH performance in the HIFT were significantly higher than MITT (P<0.05). MDA and H 2 O 2 in the HIFT decreased significantly (P<0.05), but no significant changes were observed in the MITT (P>0.05). CAT activity decreased significantly (P<0.05), while GPx activity increased significantly (P<0.05) in both groups. 8-OHDG did not show significant changes in both groups (P>0.05). 8 weeks of HIFT did not cause greater OS compared to MITT, while could improve physical performance parameters. Trial registration : The present study was a randomized controlled trial (registration number: IRCT20190530043762N1, 25/09/2019, Iran)