The acute respiratory response to blood-flow restriction resistance exercise in healthy adults: A randomized...

This study compared acute respiratory responses to low-load blood flow restriction resistance exercise (LL-BFR) and traditional high-load resistance exercise (HL-TRA) in healthy individuals. A randomized crossover design with a 48-h washout was used. Participants completed LL-BFR (30% one repetition maximum [1RM], 70% limb occlusion pressure [LOP]) and HL-TRA (70% 1RM, no occlusion) on a leg press. HL-TRA involved 3 sets of 12 repetitions; LL-BFR included 4 sets (15, 30). Respiratory parameters were measured breath-by-breath. Ratings of perceived breathing effort and leg exertion (0-10 scale) were recorded. Data were analyzed using linear mixed models. Twenty-four participants (8 males, 16 females) completed the study. LL-BFR resulted in lower minute ventilation (VE, primary outcome) by -3.32 L/min (95% CI: -4.55 to -2.08), oxygen consumption by -0.12 L/min (95% CI: -0.15 to -0.09), carbon dioxide production by -0.16 L/min (95% CI: -0.19 to -0.13), and perceived breathing effort by -1.2 units (95% CI: -1.5 to -0.8) compared to HL-TRA. Perceived leg exertion was higher with LL-BFR (1.8 units; 95% CI: 1.3 to 2.2). LL-BFR elicited lower respiratory responses and reduced perceived breathing effort than HL-TRA, despite greater leg discomfort.