Fisher NM, DR Pendergast and E Calkins. Maximal Isometric
Torque of Knee Extension as a Function of Muscle Length in Subjects
of Advancing age. Arch Phys Med Rehabil 71(10):729-734,
Many neuromuscular diseases are associated with muscle weakness.
Assessment of this weakness by manual muscle testing or with hand-held
equipment has been criticized. Furthermore, muscle length influences
peak force development. One hundred fifty-three female and 116 male
asymptomatic subjects between the ages of 20 and 80 (approximately
20 per decade) were studied. Maximal strength of the quadriceps
group was determined isometrically, on a specially designed bench,
at 3 hip angles (45 degrees, 90 degrees, and 180 degrees of extension),
which represent three rectus femoris muscle lengths. Maximal strength
was observed at a hip angle of 180 degrees and did not decrease
significantly from 20 to 50 years of age, although the values for
the male and female subjects over 50 years were significantly decreased
(approximately 15% per decade). The increase in strength as the
muscle was lengthened from 45 degrees to 180 degrees hip angle was
about 80% (of the force at 45 degrees) in 20-year-olds; strength
decreased progressively with age to a value of approximately 50%
in the 70-year-olds. This greater reduction in maximal strength
at longer quadriceps muscle lengths has functional significance
in rising from a chair, climbing stairs, and eventually, walking
R, NM Fisher, A Veicsteinas, DR Pendergast. Aerobic
Training and Cardiovascular Responses at Rest and during Exercise
in Older Men and Women. Med Sci Sports Exerc 34:700-708,
DR, NM Fisher and E Calkins. Cardiovascular, neuromuscular,
and metabolic alterations with age leading to frailty .
J Gerontol: Biol Sci 48(Special Issue):61-67, 1993.
R, S Milesi, NM Fisher, DR Pendergast, A Veicsteinas.
Heart Rate Variability during Dynamic Exercise in Elderly
Males and Females. Eur J Appl Physiol 82(1-2):8-15, 2000.
NM, DR Pendergast. Improved cardiac output after exercise
in the head-down tilt position in elderly subjects. Gerontologist
39 Special Issue I:466, 1999.
NM, DR Pendergast and E Calkins. Muscle Rehabilitation in
Impaired Elderly Nursing Home Residents. Arch Phys Med
Rehabil 72(3):181-185, 1991.
DR, E Calkins, NM Fisher and R Vickers. Muscle Rehabilitation
in Nursing Home Residents with Cognitive Impairment: a Pilot Study.
Am J Alzheimer Care Rel Dis July/August:: 20-25, 1987.
© Copyright 2001, 2002, 2003, 2004, 2005 Rehabilitation Physiology Lab