1. JJ Zachwieja, PhD, is Assistant Professor and Chief, Exercise and Nutrition Program, Pennington Biomedical Research Center, Baton Rouge, La
2. KE Yarasheski, PhD, is Assistant Professor in Medicine, Washington University Medical Center, Division of Metabolism, Endocrinology, and Diabetes, Claude Pepper Older Americans Independence Center, Campus Box 8127, St Louis, MO 63110 (USA).