Cluster Training With Blood Flow Restriction in Competitive 200-m Freestyle Swimmers

This study evaluated whether adding blood flow restriction (BFR) to cluster-based training could improve swimming performance and selected physiological responses in competitive swimmers. Twenty competitive swimmers were assigned using a matched, non-randomized design to either an experimental group performing cluster training combined with BFR or a control group performing the same cluster training without BFR. The intervention lasted 8 weeks, with five training sessions per week. The primary outcome was 200-m freestyle performance time. Secondary outcomes included serum concentrations of fibroblast growth factor-2 (FGF-2) and vascular endothelial growth factor-A (VEGF-A), standing long jump performance, mean 50-m split time during a 150-m swimming test, and repetitions completed during a cadence-controlled Burpee test. The study was designed to determine whether BFR provided additional performance and physiological benefits beyond cluster training alone.