High-intensity interval training (HIIT) is increasingly employed in a variety of clinical settings due to the growing evidence of increased efficacy compared with moderate-intensity exercise for a range of health and physical function and exercise outcomes. In this brief review, we highlight the recent findings from randomized trials, discuss the evidence and rationale for the greater physiological adaptations to HIIT, and identify future areas of research that will aid in the optimization of HIIT as an adjunctive therapy in the management of heart failure.