Background
The role of strength training in peripheral arterial disease (PAD) is unclear. Benefits of supervised treadmill exercise in PAD patients without intermittent claudication (IC) are not established.
Objective
To determine whether supervised treadmill exercise and lower extremity resistance training, respectively, improve functional performance compared to a control group in PAD persons with and without IC.
Design
Randomized controlled clinical trial performed between 4/1/04 and 8/19/08.
Participants
156 people with PAD (ankle brachial index ≤ 0.95), including 81.4% without IC.
Measurements
Primary outcomes were six-minute walk performance and the short physical performance battery (SPPB). Additional outcomes were brachial artery flow-mediated dilation (FMD), treadmill walking performance, the Walking Impairment Questionnaire (WIQ), and the Short-Form 36 Physical Functioning score (SF-36 PF).
Interventions
Three parallel arms: supervised treadmill exercise, supervised lower extremity resistance training, and a control group.
Results
Compared to control, the treadmill exercise group increased six-minute walk distance (+35.9 meters, 95% confidence interval (CI), +15.3 to +56.5; P <0.001), while the resistance trained group did not improve (+12.4 meters, 95% CI, −8.42 to +33.3; P=0.24). Neither exercise group improved the SPPB. Compared to control, treadmill exercise improved brachial artery FMD (+1.53%, 95% CI, +0.35 to +2.70, P=0.018), time on treadmill (+3.44 minutes, 95% CI, +2.05 to +4.84; P<0.001), the WIQ distance score P=0.015), and the SF-36 PF score (P=0.02). Compared to control, resistance training improved time on treadmill (+1.98 minutes, 95% CI, +0.56 to +3.39; P=0.007), the WIQ distance score (P=0.02), the WIQ stair climbing score (P=0.02), and the SF-36 PF score (P=0.04).
Conclusion
Supervised treadmill exercise improved six-minute walk distance, treadmill walking performance, brachial artery FMD, and quality of life, but not the SPPB, in PAD participants with and without classic IC symptoms. Resistance training improved treadmill walking performance, quality of life, and stair climbing ability in patients with PAD.