The effect of exercise training on quality of life and exercise capacity was studied in 67 patients with mild to moderate chronic heart failure (CHF; age: 65.6+/-8.3 years; left ventricular ejection fraction: 26.5+/-9.6%). Patients were randomly allocated to either a training group or to a control group. After intervention a significantly larger decrease in Feelings of Being Disabled (a subscale of the Heart Patients Psychological Questionnaire) and a significantly larger increase in the Self-Assessment of General Well-Being (SAGWB) were observed in the training group. Exercise time and anaerobic threshold were increased in the training group only. The increase in exercise time was related to both Feelings of Being Disabled and SAGWB. We conclude that supervised exercise training improves both quality of life and exercise capacity and can be safely performed by chronic heart failure patients.