Exercise Training for Heart Failure

We have known for many years of the benefits of an exercise component in cardiac rehabilitation. It was initially thought that significant left ventricular impairment was a contraindication to participation in such programs. In fact, in heart failure, there was a vogue for and reports of the beneficial effects of prolonged bed rest.1 It is against this background that a few challenging reports emerged in the early 1980s that selected patients with significant left ventricular impairment had in fact participated in exercise programs and had achieved training responses with increased exercise capacity.2 3 4 It was not until the late 1980s, however, that the first reports of training patients with a history of chronic heart failure (CHF) emerged.5 6 Pioneering work from Duke University showed a significant enhancement in exercise capacity and ancillary physiological benefits, including reduced lactate production, improved use of ventilatory reserve, and increased leg blood flow during progressive exercise.5 6 This was quickly followed by the first prospective controlled trial of exercise training in CHF, an 11-patient crossover study of home-based exercise training using a cycle ergometer for 8 weeks versus a similar period of activity restriction.7 The result was an improvement in exercise capacity and an improvement in questionnaire-based heart failure–related symptoms. The era of training as a treatment of heart failure had begun.In the decade following these first reports, there have been a profusion of small trials and a long list of impressive physiological gains that could be achieved. These included increased peak oxygen consumption,8 9 10 an increase in peak cardiac output (in some8 but not all trials), and improvement in the autonomic control of the circulation with a reduction in sympathetic nervous system activity …