1. From the Department of Kinesiology (T.O.O., D.A.P., S.J.P., J.M.H.), University of Maryland, College Park, Md; the Section of Geriatrics (T.O.O.), Department of Medicine, Howard University Hospital, Washington DC; Biochemistry of Aging Laboratory (C.L., T.P.), College of Medicine and Health and Human Performance, University of Florida, Gainesville, Fla; and the Department of Human Genetics (R.E.F.), University of Pittsburgh, Graduate School of Public Health, Pittsburgh, Pa.