Systemic oxygen consumption (V_ O2) has traditionally been the gold standard for assessing aerobic metabolic demand. However, under conditions that alter normal blood flow or ventilation, such as blood flow restriction (BFR), V_ O2 may no longer reflect metabolic cost. The purpose of this study was to evaluate the total oxygen requirement (VO2) of walking with and without BFR, including in-exercise VO2 and excess postexercise oxygen consumption (EPOC). In a randomized crossover design, 18 recreationally active participants completed three, 3-min treadmill walking bouts, each separated by a 1-min standing rest to simulate a typical repeated BFR protocol. In the BFR condition, tourniquets were applied to the upper thighs at 100% of the limb occlusion pressure throughout the interval protocol and removed for 15 min of seated recovery. Expired gasses were recorded continuously. Walking VO2 was initially lower in the BFR condition compared with control (CON) (P ¼ 0.0002), but reversed over time, with BFR producing a greater total walking VO2 (BFR: 16,638 ± 2,157 mL; CON: 15,219 ± 2,444 mL; P ¼ 0.0006) and higher EPOC (BFR: 7,789 ± 837 mL; CON: 6,267 ± 1,102 mL; P textless 0.0001). The relative contribution of EPOC to total oxygen demand was elevated with BFR (BFR: 32.0 ± 2.8%; CON: 29.2 ± 2.1%; P ¼ 0.0012), together indicating a time-dependent shift in V_ O2. This suggests that acute, rate-based V_ O2 does not fully capture the true metabolic demands of BFR exercise. Researchers should instead consider the total oxygen and recovery when interpreting metabolic load during BFR.