Effects of Walking Exercise at a Pace With Versus Without Ischemic Leg Symptoms on Functional Performance Measures in People With Lower Extremity Peripheral Artery Disease: The LITE Randomized Clinical Trial

BACKGROUND: In people with peripheral artery disease, post hoc analyses of the LITE (Low Intensity Exercise Intervention in Peripheral Artery Disease) randomized trial were conducted to evaluate the effects of walking exercise at a pace inducing ischemic leg symptoms on walking velocity and the Short Physical Performance Battery, compared with walking exercise without ischemic leg symptoms and compared with a nonexercising control group. METHODS AND RESULTS: Participants with peripheral artery disease were randomized to: home‐based walking exercise that induced ischemic leg symptoms; home‐based walking exercise conducted without ischemic leg symptoms; or a nonexercising control group for 12 months. Outcomes were change of walking velocity over 4 m and change of the Short Physical Performance Battery (0–12, with 12=best) at 6‐ and 12‐month follow‐up. A total of 264 participants (48% women, 61% Black race) were included. Compared with walking exercise without ischemic symptoms, walking exercise that induced ischemic symptoms improved change in usual‐paced walking velocity over 4 m at 6‐month (0.056 m/s [95% CI, 0.019–0.094 m/s]; P<0.01) and 12‐month follow‐up (0.084 m/s [95% CI, 0.049–0.120 m/s]; P<0.01), change in fast‐paced of walking velocity over 4 m at 6‐month follow‐up (P=0.03), and change in the Short Physical Performance Battery at 12‐month follow‐up (0.821 [95% CI, 0.309–1.334]; P<0.01). Compared with control, walking exercise at a pace inducing ischemic symptoms improved change in usual‐paced walking velocity over 4 m at 6‐month follow‐up (0.066 m/s [95% CI, 0.021–0.111 m/s]; P<0.01). CONCLUSIONS: In people with peripheral artery disease, those who walked for exercise at a comfortable pace without ischemic leg symptoms slowed their walking speed during daily life and worsened the Short Physical Performance Battery score, a potentially harmful effect, compared with people who walked for exercise at a pace inducing ischemic leg symptoms. Compared with a control group who did not exercise, home‐based walking exercise at a pace inducing ischemic leg symptoms significantly improved change of walking velocity over 4 m at 6‐month follow‐up, but this benefit did not persist at 12‐month follow‐up. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02538900.