Impact of Exercise Training at Different Intensity Levels on Cardiac Function and Exercise Capacity in Patients with Chronic Heart Failure: A Prospective Cohort Study.

OBJECTIVE

To investigate training at different intensity levels on cardiac function, exercise capacity, and health-related quality of life in patients with chronic heart failure.

METHODS

This prospective cohort study enrolled patients with chronic heart failure at Beijing Rehabilitation Hospital, Beijing, China from January 2018 to January 2020. Participants received conventional therapy (non-exercise group) or therapy plus cycle ergometer exercises at an intensity of 80% anaerobic threshold (EA group) and Δ50% power above anaerobic threshold (EB group) for 12 weeks. The primary outcome was peak oxygen uptake.

RESULTS

Forty-five patients (15/group) completed the study without serious complications. Exercise training at an intensity of Δ50% power above anaerobic threshold had better effects on exercise capacity than exercise at an intensity of 80% anaerobic threshold, as shown by a greater improvement in peak oxygen uptake (20.3 ± 4.1 vs 16.8 ± 3.2 mL/min/kg), peak O2 pulse (12.5 ± 2.3 vs 10.1 ± 2.1 mL/beat), and peak workload (123.1 ± 26.9 vs 102.8 ± 29.5 W) in patients with chronic heart failure (all p < 0.001). Exercise improved the 6-min walk test distance (control: 394.0 ± 74.1; EA: 481.4 ± 89.4; EB: 508.9 ± 92.5 m; p < 0.001) and health-related quality of life (control: 40.7 ± 12.3; EA: 16.2 ± 8.6; EB: 11.5 ± 6.4; p < 0.001).

CONCLUSION

Compared with an intensity of 80% anaerobic threshold, exercise training at an intensity of Δ 50% power above anaerobic threshold was safe and had better effects on cardiac function, exercise capacity, and health-related quality of life.