PROJECT SUMMARY/ABSTRACT Heart failure with preserved ejection fraction (HFpEF) is one of the greatest treatment challenges in cardiovascular care today. Exercise is one of few treatments shown to benefit adults with HFpEF. Yet, to achieve and sustain the benefits of exercise, adherence is required. Recent National Heart Lung and Blood Institute (NHLBI) working groups on HFpEF and exercise in heart failure highlighted high priority areas for future study including examining strategies and interventions to promote exercise initiation and adherence, testing interventional mechanisms to improve adherence to exercise, identifying clinically meaningful outcomes for heart failure trials beyond mortality, and examining longitudinal changes in inflammatory biomarkers to better understand correlates to clinical status. Our team has successfully tested an intervention [Heart Failure Exercise and Resistance Training (HEART) Camp] that significantly improves long-term adherence to moderate intensity exercise (≥120 minutes of exercise at a heart rate reserve of 40-80%) in stable, chronic heart failure. Adherence was moderated by ejection fraction and a secondary analysis of our HFpEF subgroup showed promising long- term exercise adherence. We now propose a sufficiently powered randomized controlled trial to test the efficacy of 2 interventions in achieving long-term exercise adherence in adults with HFpEF. Our overall objectives align with NHLBI priorities and work toward achieving our long-term goal to promote adherence to exercise in HFpEF: (a) evaluate the effects of theory-based training and coaching interventions on long-term adherence to exercise, (b) identify minutes of moderate-intensity exercise that relate to clinically meaningful change in patient-reported outcomes, (c) evaluate interventional mechanisms and interim clinical events as mediators of adherence behaviors, and (d) examine the cost of intervention delivery. To meet these objectives, we propose a 3-group randomized controlled trial to compare 2 interventions, HEART Camp (in-person) to HEART Camp Connect (virtual) to each other and to enhanced usual care in adults with HFpEF. The proposed study incorporates several innovations: 1. We are the first to: test the effects of behavioral interventions designed to promote long-term exercise adherence in HFpEF using an objective measure of adherence, attempt to define a benchmark of minutes of exercise needed to achieve a clinically meaningful change, and assess exercise intervention cost; and 2. We incorporate technical innovations including a web application for real-time capture of exercise data, an innovative analytic approach that examines the influence of interim clinical events on adherence, a HFpEF algorithm and large-scale inflammatory assays. These innovations challenge the current paradigm and help to reach new horizons in HFpEF science. Our approach, which combines well-studied theoretical mechanisms delivered with virtual coaching and training tested against in-person coaching and training, will allow us to better understand exercise adherence in HFpEF. This study will have a critical impact by lessening non-adherence as a barrier to progress in the clinical care of adults with HFpEF through regular exercise training.

PROJECT NARRATIVE Exercise is one of few treatments shown to benefit adults with heart failure with preserved ejection fraction (HFpEF). Yet, exercise is one of the most challenging treatments for adults with HFpEF to start and continue over time. This study tests two behavioral interventions, Heart Failure Exercise and Resistance Training (HEART) Camp (in-person) and HEART Camp Connect (virtual), designed to promote adherence to exercise and improve physical function, inflammation, symptoms, and quality of life.