Influence of High-Intensity Interval Training Versus Continuous Training on Functional Capacity in Individuals With Heart Failure A SYSTEMATIC REVIEW AND META-ANALYSIS

Introduction: Cardiac rehabilitation programs reduce the risk of death and acute events related to the disease through the association of various modalities of exercise. When implemented in high-intensity interval training (HIIT) programs, it may allow for gradual adaptation of the skeletal muscles to greater exercise intensities. The present systematic review aimed to determine whether HIIT promoted a greater increase in exercise tolerance in comparison with continuous aerobic training in individuals with heart failure. Methods: A systematic search for articles indexed in the PubMed/MEDLINE, LILACS, SciELO, PEDro, Scopus, and Web of Science databases was carried out. The descriptors used for the search followed the description of the MeSH/DeCS terms with no language or year of publication restrictions. When possible, a meta-analysis was performed and the quality of the evidence was evaluated using the GRADE scale. Results: The broad search strategy resulted in 5258 titles, and a total of 7 articles were included in the qualitative synthesis. A low quality of evidence was observed demonstrating that interval training is superior to continuous aerobic training for improving peak oxygen uptake, which reflects an increase in functional capacity of these individuals and moderate quality of evidence regarding improved quality of life and left ventricular ejection fraction. Conclusion: High-intensity interval training and continuous training provide benefits for patients, however, the quality of evidence still does not allow us to indicate whether there is a superiority of HIIT over conventional continuous exercise training using the variables analyzed.