Aging of skeletal muscle: a 12-yr longitudinal study

1 Department of Physical Medicine and Rehabilitation, Harvard Medical School and Spaulding Rehabilitation Hospital, Boston 02114; 2 Nutrition, Exercise Physiology, and Sarcopenia Laboratory, Jean Mayer US Department of Agriculture Human Nutrition Research Center on Aging, Tufts University, Medford 02155; 3 Department of Health Sciences, Sargent College of Health and Rehabilitation Sciences, Boston University, Boston, Massachusetts 02215; 4 School of Exercise and Sport Science, University of Sydney, Sydney, New South Wales 2006, Australia; and 5 Donald W. Reynolds Department of Geriatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72204 The present study examines age-related changes in skeletal muscle size and function after 12 yr. Twelve healthy sedentary men were studied in 1985-86 (T1) and nine (initial mean age 65.4 ± 4.2 yr) were reevaluated in 1997-98 (T2). Isokinetic muscle strength of the knee and elbow extensors and flexors showed losses ( P