Functional training improves peak oxygen consumption and quality of life of individuals with heart failure: a randomized clinical trial

BACKGROUND

Functional training may be an effective non-pharmacological therapy for heart failure (HF). This study aimed to compare the effects of functional training with strength training on peak VO₂ and quality of life in individuals with HF.

METHODS

A randomized, parallel-design and examiner-blinded controlled clinical trial with concealed allocation, intention-to-treat and per-protocol analyses. Twenty-seven participants with chronic HF were randomly allocated to functional or strength training group, to perform a 12-week physical training, three times per week, totalizing 36 sessions. Primary outcomes were the difference on peak VO₂ and quality of life assessed by cardiopulmonary exercise testing and Minnesota Living with Heart Failure Questionnaire, respectively. Secondary outcomes included functionality assessed by the Duke Activity Status Index and gait speed test, peripheral and inspiratory muscular strength, assessed by hand grip and manovacuometry testing, respectively, endothelial function by brachial artery flow-mediated dilation, and lean body mass by arm muscle circumference.

RESULTS

Participants were aged 60 ± 7 years, with left ventricular ejection fraction 29 ± 8.5%. The functional and strength training groups showed the following results, respectively: peak VO₂ increased by 1.4 ± 3.2 (16.9 ± 2.9 to 18.6 ± 4.8 mL.kg^-1.min^-1; p time = 0.011) and 1.5 ± 2.5 mL.kg^-1.min^-1 (16.8 ± 4.0 to 18.6 ± 5.5 mL.kg^-1.min^-1; p time = 0.011), and quality of life score decreased by 14 ± 15 (25.8 ± 14.8 to 10.3 ± 7.8 points; p time = 0.001) and 12 ± 28 points (33.8 ± 23.8 to 19.0 ± 15.1 points; p time = 0.001), but no difference was observed between groups (peak VO₂: p interaction = 0.921 and quality of life: p interaction = 0.921). The functional and strength training increased the activity status index by 6.5 ± 12 and 5.2 ± 13 points (p time = 0.001), respectively, and gait speed by 0.2 ± 0.3 m/s (p  time = 0.002) in both groups.

CONCLUSIONS

Functional and strength training are equally effective in improving peak VO₂, quality of life, and functionality in individuals with HF. These findings suggest that functional training may be a promising and innovative exercise-based strategy to treat HF.

TRIAL REGISTRATION

NCT03321682. Registered date: 26/10/2017.

Cardiopulmonary exercise capacity and quality of life of patients with heart failure undergoing a functional training program: study protocol for a randomized clinical trial

BACKGROUND

Exercise intolerance is a common finding in heart failure that generates a vicious cycle in which the individual starts to limit his activities even more due to progressive fatigue. Regular physical exercise can increase the cardiopulmonary exercise capacity of these individuals. A new approach to physical exercise, known as functional training, could improve the oxygen consumption and quality of life of patients with heart failure; however, there is no information about the effect of this modality of exercise in this patient population. This randomized trial will compare the effects of 36 sessions of functional training versus strength training in heart failure patients.

METHODS

This randomized parallel-design examiner-blinded clinical trial includes individuals of both sexes aged ≥40 years receiving regular follow-up at a single academic hospital. Subjects will be randomly allocated to an intervention group (for 12-week functional training) or an active comparator group (for 12-week strength training). The primary outcomes will be the difference from baseline to the 3-month time point in peak oxygen consumption on cardiopulmonary exercise testing and quality of life assessed by the Minnesota Living with Heart Failure Questionnaire. Secondary outcome measures will include functionality assessed by the Duke Activity Status Index and gait speed test; peripheral and inspiratory muscular strength, assessed by hand grip and manovacuometry testing, respectively; endothelial function by brachial artery flow-mediated dilation; lean body mass by arm muscle circumference; and participant adherence to the exercise programs classified as a percentage of the prescribed exercise dose.

DISCUSSION

The functional training program aims to improve the functional capacity of the individual using exercises that relate to his specific physical activity transferring gains effectively to one's daily life. In this context, we believe that that functional training can increase the cardiopulmonary exercise capacity and quality of life of patients with heart failure. The trial has been recruiting patients since October 2017.

TRIAL REGISTRATION

NCT03321682. Registered on October 26, 2017.