Resting muscle VO( 2) consumption (rmVO(2)) as measured by near-infrared spectroscopy (NIRS) has been poorly studied in peripheral arterial disease (PAD). We studied the feasibility of its assessment in a clinical setting, compared values from PAD and healthy participants, and identified factors affecting rmVO( 2) in PAD. A total of 119 PAD patients with claudication and 30 healthy participants were enrolled. Ankle brachial index (ABI), adipose tissue thickness, and rmVO(2) in the gastrocnemius after venous (rmVO(2)ven) or arterial (rmVO(2)art) occlusion were measured with NIRS. Compared to rmVO(2)art, rmVO(2)ven determination was less painful (P = .001), with higher values (P < .0001). rmVO(2)ven of PAD patients was not significantly different from healthy participants and was inversely correlated with the corresponding ABI (P = .018). rmVO(2)ven from severely diseased legs was higher than values from borderline/moderately diseased legs (P = .003). The determination of rmVO(2)ven by NIRS is suitable for the clinical setting and allows noninvasive quantification of a compensatory peripheral adaptation in patients with PAD.