Iñigo San-Millán1,2,3, George A Brooks4. 1. Department of Human Physiology and Nutrition, University of Colorado, Colorado Springs, CO, USA. inigo.sanmillan@cuanschutz.edu. 2. Department of Medicine, Division of Endocrinology, Metabolism and Diabetes, University of Colorado Anschutz Medical Campus, Aurora, CO, USA. inigo.sanmillan@cuanschutz.edu. 3. Department of Medicine, Division of Medical Oncology, University of Colorado Anschutz Medical Campus, Aurora, CO, USA. inigo.sanmillan@cuanschutz.edu. 4. Exercise Physiology Laboratory, Department of Integrative Biology, University of California, Berkley, CA, USA.