Purpose: To determine if eccentric exercise was effective, safe and feasible in increasing function and quality of life in people with heart failure compared to usual care and a waitlist control group.
Methods: A prospective, three-armed, parallel-design, assessor-blind, pilot randomised controlled trial with 1:1:1 allocation. Forty-seven participants (16 female; mean age 66 years) with mild to moderate heart failure were randomly allocated to either eccentric exercise, concentric exercise or a waitlist control group. Participants in the exercise groups completed twice-weekly exercise for eight weeks. Primary outcome was walking capacity. Secondary outcomes were quality of life, leg strength and fatigue. Outcomes were assessed at baseline, post intervention and three-month follow-up. Attendance, tolerability and adverse events were used to determine safety and feasibility.
Results: Intention-to-treat analysis showed no differences between eccentric exercise and either concentric exercise or waitlist for any outcome. Per-protocol analysis found improvements identified by the Minnesota living with heart failure questionnaire were significantly greater post-intervention for eccentric exercise compared to concentric exercise (-17.99 units, 95% confidence interval -35.96 to -0.01). No major adverse events were reported.
Conclusion: In this small trial, eccentric exercise did not demonstrate superior outcomes to concentric exercise or a waitlist control group.
Clinical trial registration: The protocol for this trial was registered at clinicaltrials.gov, registration number: NCT02223624, registration date: 22 August 2014.IMPLICATIONS FOR REHABILITATIONRegular physical activity and referral to rehabilitation is recommended for people with chronic heart failure, however exercise can be challenging for this group.Eccentric exercise was safe and tolerable for participants with heart failure.Documentation of exercise progression is important to demonstrate a dose-response relationship.In this study there were no differences between groups who received eccentric exercise, concentric exercise or no exercise.
Keywords: Chronic heart failure; eccentric exercise; exercise; function; heart failure; quality of life; rehabilitation.