1. From the Division of Endocrinology, Metabolism & Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO (X.L., S.B.R., L.M., R.E.O.); Program in Physical Therapy, Washington University School of Medicine, St. Louis, MO (S.B.R.); and Division of Biostatistics, Washington University School of Medicine, St. Louis, MO (M.W.).