Influence of blood flow restriction cuff width on acute metabolic, perceptual, and landing responses to low-load resistance exercise in trained long jump athletes.

BACKGROUND: Blood flow restriction (BFR) is used with low-load resistance exercise, but acute responses may depend on cuff width when pressure is prescribed relative to arterial occlusion pressure (AOP). AIM: To compare acute metabolic, perceptual, and landing-related responses among No-BFR, 6-cm BFR, and 12-cm BFR conditions in trained male long-jump athletes. METHODS: Twenty-two athletes completed the three conditions in a randomized crossover design. Participants performed Smith-machine half squats at 30% of one-repetition maximum using four sets of 30, 15, 15, and 15 repetitions with 30-s inter-set rest. Cuffs were maintained at 40% of cuff-specific AOP. Blood lactate was measured before, immediately after, and 5 min after exercise. Rating of perceived exertion (RPE) and numerical pain rating scale (NPRS) scores were recorded after each set. Drop-jump (DJ) height, loading rate, and center-of-pressure (COP) sample entropy were measured before and after exercise. RESULTS: BFR produced higher blood lactate, RPE, and NPRS than No-BFR, particularly during later assessments. Significant condition-by-time/set interactions were observed for blood lactate (F(2.24,47.12)=14.101, p<0.001, ηp²=0.402), NPRS (F(4.34,91.04)=4.839, p=0.001, ηp²=0.180), DJ height (F(1.76,37.04)=20.163, p<0.001, ηp²=0.490), loading rate (F(1.87,39.31)=3.850, p=0.032, ηp²=0.155), and COP sample entropy (F(1.51,31.65)=7.521, p=0.004, ηp²=0.264); the RPE interaction was not significant (p = 0.094). Following BFR, DJ height decreased, whereas loading rate and COP sample entropy increased. The 12-cm condition generally produced the largest responses, although direct cuff-width differences were not uniform. CONCLUSIONS: Cuff width influenced acute metabolic, perceptual, and post-exercise landing responses during low-load BFR exercise. These acute findings do not establish superior long-term training adaptations.