LAUSR

To compare the physiological and perceptual responses during fixed‐power and perceptually regulated cycling, both without and with blood flow restriction (CONPWR, BFRPWR, CONRPE and BFRRPE). Twelve recreationally active men cycled for 10 min at the power corresponding to the first ventilatory threshold or, for CONRPE and BFRRPE, the perceived exertion level reported during CONPWR. Blood flow restriction was set at 60% of estimated arterial occlusion pressure. Ventilatory measures and heart rate were averaged into 2‐min blocks. Perceived exertion, effort, muscular discomfort and cuff pain were recorded every 2 min (0–10 scale). Blood lactate was measured pre‐exercise, post‐exercise, and 2 min post‐exercise. The BFRPWR trial elicited greater physiological and perceptual responses compared to all other conditions. Oxygen consumption during BFRRPE was lower than CONPWR (−19.2 ± 20.6%, p < 0.001) and CONRPE (−6.7 ± 9.3%, p = 0.007). Heart rate during CONPWR was greater than BFRRPE (8.2 ± 9.8%, p < 0.001) and CONRPE (9.4 ± 6.5%, p < 0.001). Blood lactate concentration was not different between CONPWR, CONRPE and BFRRPE; yet was greater during fixed‐power compared to fixed‐RPE trials (31.5 ± 25.6%, p < 0.001). Muscular discomfort was not different between BFRRPE and CONPWR (2.4 ± 1.1 au), yet both were greater compared to CONRPE (1.8 ± 1.5 au, p < 0.001). Cuff pain was greater during BFRPWR (3.3 ± 1.7 au) compared to BFRRPE (2.2 ± 1.1 au, p < 0.001). Prescribing aerobic BFR cycling at a fixed power output increases physiological strain, yet discomfort and pain are also heightened, which may limit its use in healthy adults. The fixed‐RPE method appears to balance the physiological and perceptual demands and thus could be a viable alternative if a fixed power output approach is intolerable.