7. Project Summary/Abstract We have developed a nutritional formulation of amino acids called UpBeat that is designed to promote physical function and quality of life in older individuals with heart failure. Reduced exercise capacity is a prominent clinical feature of heart failure. This leads to progressive muscle weakness and a vicious cycle of sedentary behavior, weight gain, and subsequent development of metabolic abnormalities and sarcopenia. The impairment of physical function limits the health-related quality of life. Because of the limited capacity for exercise in most individuals with heart failure and the failure of drug therapy to completely resolve the symptoms, a wide variety of nutritional products have been marketed for therapy for heart failure. The data supporting the value of nutritional supplements for heart failure currently on the market either do not exist or are equivocal. UpBeat differs from most nutritional products for heart failure because it targets skeletal muscle function, and its value is supported by strong preliminary data. It is the goal of the current proposal to perform a randomized clinical trial (RCT) to test the ability of UpBeat to improve physical function and quality of life in older individuals with heart failure. The Specific Aims of this Phase II project are as follows: Specific Aim #1: We propose that 16 weeks of regular consumption of UpBeat will improve physical function in individuals with heart failure. Specific Aim #2: We propose that regular consumption of UpBeat will improve health-related quality of life. Specific Aim #3: We propose that regular consumption of UpBeat will lower the fasting concentrations of blood glucose and insulin, as well as triglycerides and low-density lipids. Positive results of this randomized clinical trial will provide evidence of the benefits of UpBeat for therapy of heart failure. In a more general sense, positive results will substantiate the benefits of targeting skeletal muscle function as a means to improve physical function and quality of life in heart failure.