Eleven patients with chronic heart failure secondary to ischaemic heart disease (mean [SEM] age 63.0 [2.3] years; left ventricular ejection fraction 19 [8]% undertook 8 weeks of home-based bicycle exercise training and 8 weeks of activity restriction (rest) in a physician-blind, random-order, crossover trial. Training increased exercise duration from 14.2 (1.1) min to 16.8 (1.3) min and peak oxygen consumption from 14.3 (1.1) ml.min-1.kg-1 to 16.7 (1.3) ml.min-1.kg-1. Heart rates at submaximum workloads and rate-pressure products were significantly reduced by training, and there was also a significant improvement in patient-rated symptom scores. No adverse events occurred during the training phase. Thus home-based physical training programmes are feasible even in severe chronic heart failure and have a beneficial effect on exercise tolerance, peak oxygen consumption, and symptoms. The commonly held belief that rest is the mainstay of treatment of chronic heart failure should no longer be accepted.