Performance and injury-related effects of low-load blood flow restriction training in amateur soccer players: a randomized controlled trial

Abstract

Background Blood flow restriction (BFR) has gained interest in its application in exercise and potential benefits. This study aimed to investigate the effects of low-load, low-frequency BFR training compared with traditional high-intensity training on soccer-related performance outcomes and injury indicators in amateur athletes. Methods Twenty licensed male soccer players competing in a university-level league were randomized to either a BFR group (n = 10, 22.3 +/- 1.3 years) or a control group (n = 10, 22.1 +/- 1.8 years) for 6 weeks of training. Pre- and post-intervention assessments included muscle strength-endurance (isokinetic dynamometer), power (vertical jump test), aerobic endurance (Yo-Yo level 1 test), speed-agility (T test, Y-shaped reactive agility test), dynamic balance (Y test), thigh circumference, fatigue (blood lactate, Borg scale), and sportive self-confidence. Perceived change (GROC) was assessed post-intervention. Injury data were tracked for six months following the intervention. Results BFR improved dominant limb flexor strength, endurance, aerobic capacity, speed, and dynamic balance (p < 0.05, Cohen's d: 0.40-1.06). Both groups showed gains in power, agility, and self-confidence (p < 0.05, Cohen's d: BFR = 0.51-1.35; Control = 0.40-1.01), whereas hypertrophy (p = 0.026, P eta(2) = 0.24) and GROC scores (p = 0.022) were significantly higher in the BFR group than in the control group. No differences were observed in terms of fatigue. The standard error of the mean values for significant within-group changes ranged from 0.03 to 8.64. Although the injury rate was lower in the BFR group, this trend was not significant (p > 0.05). ConclusionBF R appears to be a feasible, load-efficient, and well-tolerated approach to improve performance parameters in amateur soccer players, with potential benefits for lower-limb injury prevention.