BACKGROUND: Peripheral artery disease (PAD) significantly affects patient prognosis, leading to a rapid decline in physical function and health-related quality of life. PAD impacts walking economy, causing higher oxygen uptake during submaximal walking, which is crucial for evaluating walking performance and aerobic endurance. RESEARCH QUESTION: How do arm-ergometry supervised exercise training (AEx) and treadmill exercise training (TEx) compare in their effects on walking economy, and what clinical characteristics and outcomes influence the degree of this improvement? METHODS: This study is an ancillary investigation of the ARMEX trial, a single-center, single-blinded, parallel groups, noninferiority randomized clinical trial. Patients with symptomatic PAD were randomized (1:1 ratio) either to a 12-week AEx or TEx. Walking economy was measured by oxygen uptake (V̇O RESULTS: Fifty-six patients (66 ± 8.4 years
87.5 % male) were enrolled and randomized: AEx (n = 28) and TEx (n = 28). At 12-weeks, V̇O SIGNIFICANCE: Treadmill exercise improved walking economy more than arm-ergometry in patients with PAD. Individuals with a higher BMI experience less improvement in walking economy with exercise training and might require specialized interventions.