WALKING ECONOMY AND PERFORMANCE AFTER TRAINING AND ACTIVITY RESTRICTION IN CHRONIC HEART FAILURE PATIENTS

Abstract

496 The effect of exercise training and subsequent activity restriction on performance and economy of walking was analysed in 9 male patients with chronic heart failure (age: 50.8 ± 5.5 yrs, height: 175.0 ± 5.8 cm, body mass: 75.4 ± 4.7 kg, ejection fraction: 21 ± 5%). They were submitted to a cardiopulmonary exercise test on a cycle ergometer and a 6 min - walking test on a treadmill before (A) and after three weeks of training(B) and after three weeks of activity restriction (C). The training program consisted of interval cycle (15 min, five times a week) and treadmill ergometer training (10 min, three times a week) at approximately 70% cycling VO2peak, and supplementing exercises (20 min, three times a week). During activity restriction no exercise training was done. At A, B, and C, cycling VO2peak (13.6 ± 2.2; 15.4 ± 2.9; 13.7 ± 2.4 ml·kg-1·min-1), walking VO2 (11.4± 3.1; 11.6 ± 2.5; 10.2 ± 1.7 ml·kg-1·min-1) and metabolic walking power (2.73± 1.17; 2.73 ± 0.96; 2.27 ± 0.79 W·kg-1) did not differ significantly. However, walking speed was higher (p < 0.05) at B (1.2 ± 0.3 m·s-1) than at A and C (0.8 ± 0.4 and 0.9 ± 0.2 m·s-1), whereas energy cost of walking was higher at A (3.41 ± 0.59 J·kg-1·m-1) than at B and C (2.28 ± 0.41 and 2.56 ± 0.48 J·kg-1·m-1). These results indicate that adequate exercise training programs contribute to favorable effects on performance and economy of motion, even without significant metabolic changes. Activity restriction related maleffects on exercise capacity, and economy of motion seem to underly different time courses.