Improved quality of life in chronic heart failure patients following local endurance training with leg muscles.

BACKGROUND: Despite reported benefits of exercising for chronic heart failure patients, limited data are available on quality of life and the effects of different modes of training. This study assessed the effects of local endurance training with knee extensor muscles on exercise tolerance and health-related quality of life in male patients with moderate, chronic heart failure.

METHODS AND RESULTS: Twenty-one patients (mean age, 60 years; range, 43-73 years) in New York Heart Association functional classes II-III (ejection fraction, 28 +/- 11%) were randomized to two training groups and one control group. Both training groups performed the same relative quantity of dynamic work with knee extensor muscles 3 days a week for 8 weeks. However, the quantity of muscle mass trained at one time and, consequently, the load on the integrated circulation differed between the groups (two-and one-leg training). Exercise capacity and perceived quality of life were assessed before and after the training or control period. Exercise tolerance increased (P < .01) in both training groups with significantly (P < .01) better improvement in submaximal exercise capacity in the two-leg group. There was no improvement in the control group. Coping capacity did not differ from the reference range and did not change during the study. Global health-related quality of life was depressed at baseline. Training improved (P < .05) health-related quality of life. Compared with the control group, the improvement of health-related quality of life subscales was more pronounced in the two-leg training group (P < .02-.005) as compared to the one-leg training group (not significant to P < .05).

CONCLUSIONS: Local muscle endurance training has beneficial effects on exercise tolerance and health-related quality of life in patients with moderate, chronic heart failure. As two-leg training showed a tendency toward better improvement in submaximal exercise capacity and in quality of life than one-leg training, the effects on quality of life appear to be exercise-related in addition to a possible placebo-related effect. Also, the effect appears to be related to the extent of muscle trained at one time.