Affiliations: [a] University of Minnesota and University of Nevada
Note: [*] Graduate student in the Physical Therapy Master's Degree Program, University of Minnesota, when this study was conducted, now Associate Scientist, Department of Neurology, University of Minnesota, Minneapolis, MN 55455.
Note: [**] Address reprint requests to Joretta M. Graves at the Department of Neurology, University of Minnesota, Minneapolis, MN 55455.
Note: [***] Graduate student in the Physical Therapy Master's Degree Program, University of Minnesota, Minneapolis, MN, when this study was conducted, now Chief Therapist for Preventive Physical Therapy at the University Hospital, Reykjavik, Iceland.
Note: [****] Assistant Professor, Department of Physical Therapy, University of Minnesota, Minneapolis, MN 55455.
Note: [*****] Associate Professor and Chairman, Department of Physical Therapy, College of Health Sciences, University of Nevada, Las Vegas, NV 89154-3021.
Abstract: The purposes of this study were to examine the relationship between physical activity level (PAL) and isometric peak torque (PT) of the knee extensor (KE) and ankle plantar flexor (PF) muscles of people 51 to 90 years of age, and to examine changes in PAL and PT by decade of age for men and women. Isometric PT of the KE and PF was measured using the Minnesota System for Isometric Muscle Strength (SIMS). Seventy-nine healthy subjects (39 men and 40 women) were tested. PT decreased as age increased. The correlation between PAL and PT was significant for both muscle groups for all 79 subjects. The women showed a progressive decline in both PAL and PT. The PAL of men changed very little until the age of 80, and decreased rapidly between the 8th and 9th decades of life. PT appeared to gradually decrease up to age 80 and decline more rapidly between the 8th and 9th decades of life. Thus PAL and PT of the knee extensors and ankle plantar flexors decrease in a similar pattern with age.
Keywords: Knee extensors, ankle plantar flexors, activity level, geriatric population
