This study should provide the mechanistic basis for and evaluation of a new nutritional formulation to be used alongside exercise training to improve muscle function and exercise performance by minimizing exercise induced metabolic deregulation in patients with Chronic Obstructive Pulmonary Disease.

Our central hypothesis is that improving the metabolic response to resistance exercise via targeted nutritional modulation with EAA enriched with HMB (EAA+HMB) will increase the gain in muscle function and exercise performance by positively influencing skeletal muscle protein homeostasis among severe COPD patients. Our rationale for the proposed research is that detailed insight in the mechanisms by which resistance exercise induces metabolic deregulations in severe COPD patients, and demonstration of the effectiveness of targeted nutritional intervention will provide opportunities for the development of innovative safe and effective nutritional approaches to improve their training response and skeletal muscle repair, leading to increased daily life physical activity. Furthermore, the proposed studies will provide supportive data of, and focus for a subsequent phase 2b/3 clinical trial to improve quality of life, and clinical outcomes of severe COPD patients. We propose to study simultaneously the following specific aim: Investigate the metabolic mechanisms by which resistance exercise induces protein catabolism in severe COPD patients as compared to healthy age and gender matched control subjects. Our working hypothesis is that patients with severe COPD (GOLD II-IV) have a metabolic signature that relates to their late (24h) post-exercise catabolic response. We will utilize an innovative IV tracer pulse approach of \> 15 labeled amino acids to enable kinetic analysis of their intracellular production, disposal and interconversion rates (fluxomics), and quantify the rates of muscle protein synthesis and breakdown. The liquid nutrition supplement will be either targeted amino acid formulation (7.0 g EAA and 1.5 g HMB (EAA+HMB)) or placebo (7.0 gram non-essential amino acids). Liquid nutrition supplement will be given to subjects according to a randomized, placebo controlled, double blind, cross-over design.