Quadriceps strength and mass peak in the third decade of life, plateau, and then decline from the fifth decade on. To examine the influence of chronic endurance training and age on lean mass and leg strength, women runners (n = 62, age 43–69 years) and sedentary participants (n = 33, age 43–66 years) were divided into 40-, 50-, and 60-year age groups. Absolute isokinetic concentric torque did not differ between runners and sedentary women (97.9 ± 19.5 and 104.6 ± 22.7 N · m, respectively, p = .18) but was different between age groups independent of exercise status (107.6 ± 18.4, 97.1 ± 19.9, and 90.1 ± 21.4 N · m, for 40s, 50s, and 60s, respectively, p < .05). Lean body mass also differed by age group (p < .05) but did not change differently among runners and sedentary women. These findings suggest that chronic endurance training might not influence the loss of muscle mass and muscle strength that occur with aging.
Tarpenning, now deceased, was with the School of Human Movement Studies, Charles Sturt University, Bathurst NSW Australia. Hawkins is with the School of Kinesiology and Nutritional Science, California State University, Los Angeles CA 90032. Marcell is with the School of Human Performance and Recreation, University of Southern Mississippi, Hattiesburg MS 39406-0001. Wiswell is with the Dept. of Biokinesiology and Physical Therapy, University of Southern California, Los Angeles, CA 90089-9006.