To compare the efficacy of treadmill exercises and stretching and resistance exercises in improving gait speed, strength, and fitness for patients with Parkinson disease. A comparative, prospective, randomized, single-blinded clinical trial of 3 types of physical exercise. The Parkinson's Disease and Movement Disorders Center at the University of Maryland and the Baltimore Veterans Affairs Medical Center, Geriatric Research Education and Clinical Center. A total of 67 patients with Parkinson disease who had gait impairment were randomly assigned to 1 of 3 arms of the trial. INTERVENTIONS; (1) A higher-intensity treadmill exercise (30 minutes at 70%-80% of heart rate reserve), (2) a lower-intensity treadmill exercise (50 minutes at 40%-50% of heart rate reserve), and (3) stretching and resistance exercises (2 sets of 10 repetitions on each leg on 3 resistance machines [leg press, leg extension, and curl]). These exercises were performed 3 times a week for 3 months. The primary outcome measures were gait speed (6-minute walk), cardiovascular fitness (peak oxygen consumption per unit time [$$ VO2], and muscle strength (1-repetition maximum strength). All 3 types of physical exercise improved distance on the 6-minute walk: lower-intensity treadmill exercise (12% increase; P=.001), stretching and resistance exercises (9% increase; P<.02), and higher-intensity treadmill exercise (6% increase; P=.07), with no between-group differences. Both treadmill exercises improved peak $$ VO2 (7%-8% increase; P<.05) more than did the stretching and resistance exercises. Only stretching and resistance improved muscle strength (16% increase; P<.001). The effects of exercise were seen across all 3 exercise groups. The lower-intensity treadmill exercise resulted in the greatest improvement in gait speed. Both the higher- and lower-intensity treadmill exercises improved cardiovascular fitness. Only the stretching and resistance exercises improved muscle strength. Therefore, exercise can improve gait speed, muscle strength, and fitness for patients with Parkinson disease. The combination of treadmill and resistance exercises may result in greater benefit and requires further investigation.
