Do low-frequency electrical myostimulation and aerobic training similarly improve performance in chronic heart failure patients with different exercise capacities?

OBJECTIVE: To confirm that electrical myostimulation is a good alternative to conventional aerobic training in patients with chronic heart failure and to compare the effects of both training programmes in patients with different exercise capacities. PATIENTS AND METHODS: A total of 44 patients with stable chronic heart failure underwent 5 weeks of exercise training, with electrical myostimulation or conventional aerobic training programmes. At baseline and after the training period, patients performed a symptom-limited cardiopulmonary exercise test and a 6-min walk test.
RESULTS: Oxygen uptake at the end of exercise (V.O2 peak) and at ventilatory threshold (V.O2 VT) increased after electrical myostimulation (p< 0.001) and conventional aerobic training (p< 0.001) training programmes. The slope of the relationship between V.O2 and workload was reduced after electrical myostimulation (p< 0.05), but not after conventional aerobic training. Recovery was improved after both training programmes (p< 0.05), and the distance walked in 6 min was increased (p< 0.001). These improvements were not statistically different between electrical myostimulation and conventional aerobic training. Moreover, electrical myostimulation induced greater improvements in patients with low exercise capacity, whereas conventional aerobic training induced improved performance in patients with average exercise capacity.
CONCLUSION: Five weeks of electrical myostimulation and conventional aerobic training exercise training produced similar improvements in exercise capacity in patients with chronic heart failure. However, electrical myostimulation appears to be more effective in patients with low exercise capacity than in those with average exercise capacity.