Does eccentric endurance training improve walking capacity in patients with coronary artery disease? A randomized controlled pilot study

Objective: To examine the effect of eccentric endurance training on exercise capacities in patients with coronary artery disease. Design: Randomized parallel group controlled study. Setting: Cardiac rehabilitation unit, Dijon University Hospital. Participants: Fourteen patients with stable coronary artery disease after percutaneous coronary intervention. Intervention: Patients followed 15 sessions of training (1 session per day, 3 days a week), either in the concentric group, following a standard programme, or in the eccentric group, performing eccentric resistance exercises using both lower limbs on a specifically designed ergometer. Main outcomes measured: Symptom-limited Vo(2), peak workload, isometric strength of leg extensor and ankle plantar flexors, distance covered during the 6-minute walk test and time to perform the 200-m fast walk test in both groups, before and after the training period. Results: Patients did not report any adverse effects and were highly compliant. All measured parameters improved in eccentric and concentric group, except for 200-m fast walk test: symptom-limited Vo(2) (+14.2% versus +4.6%), peak workload (+30.8% versus +19.3%), 6-minute walk test distance walked (+12.6% versus +10.1%) and leg extensor strength (+7% versus +13%) improved to a similar degree in both groups (P < 0.01); ankle plantar flexor strength improved in both groups with a significantly greater increase in the eccentric group (+17% versus +7%, P < 0.05). Conclusion: Patients with stable coronary artery disease can safely engage in eccentric endurance training, which appears to be as efficient as usual concentric training, with reduced oxygen consumption.