Acute Effects of Running and Blood Flow Restriction on Gas Exchange and Perceptual Responses.

Lubiak, SM, Proppe, CE, Rivera, PM, Howard, MA, Prajapati, AJ, Shah, NM, Patel, NN, Hammer, SM, Trevino, MA, Dinyer-McNeely, TK, Richardson, LD, Roth, BL, Zak, RB, and Hill, EC. Acute effects of running and blood flow restriction on gas exchange and perceptual responses. J Strength Cond Res 39(3): e436-e443, 2025-The purpose of this investigation was to examine gas exchange and perceptual responses during discrete running bouts performed at different peak running speeds with and without blood flow restriction (BFR). Twelve college-aged male subjects randomly performed four, 3-minute running bouts at 70%BFR, 80%BFR, and 90%BFR of their running speed at peak V̇o2 with BFR (applied bilaterally and most proximally on each leg) at 40% of total arterial occlusion pressure and 100%NOBFR of their running speed at peak V̇o2 without BFR. Separate 2-way, 4 (Speed [70%BFR, 80%BFR, 90%BFR, and 100%NOBFR]) × 3 (Time [120, 150, and 180 seconds]), Bayesian repeated-measure models were performed to examine differences in oxygen consumption (V̇o2), carbon dioxide production (V̇co2), and minute ventilation (V̇E) as well as ratings of perceived exertion (RPE) and pain. V̇o2, V̇co2, and V̇E increased across running speeds and was similar between the 90%BFR and 100%NOBFR speeds for V̇o2 (Meandiff = -1.49 ± 0.003 ml·kg-1·min-1; 95% HDI: -4.8 to 1.8) and V̇E (Meandiff = -6.97 ± 0.65 L·min-1; 95% HDI: -16.5 to 2.52). Ratings of perceived exertion was highest during the 90%BFR and 100%NOBFR speeds (90%BFR and 100%NOBFR > 80%BFR > 70%BFR), whereas pain was greater during the 90%BFR speed relative to the 70%BFR (Meandiff = -1.31 ± -0.20 au; 95% HDI: -2.63 to -0.0165) and 100%NOBFR (Meandiff = 1.3 ± 0.26 au; 95% HDI: 0.01-2.56) speeds. Applying BFR during 90%BFR of peak running speed induced comparable V̇o2 and V̇E responses as 100%NOBFR but was not associated with lower RPE and provoked more pain. Collectively, BFR exhibits a small, potentially negligible effect on gas exchange, which were largely speed dependent. Coaches and practitioners may consider treadmill running with BFR when reductions in exercise intensity are warranted.