Journal of Applied Physiology, Vol 63, Issue 4 1499-1503, Copyright © 1987 by American Physiological Society
Electrically evoked isokinetic plantar flexor torque in males
D. O. Thomas, M. J. White, G. Sagar and C. T. Davies
Department of Physiology and Pharmacology, Queen's Medical Centre, Nottingham, United Kingdom.
The involuntary angle-specific isokinetic plantar flexor torques of seven
male subjects aged 18-21 yr were measured using a Cybex II dynamometer
(Lumex) modified by the addition of a strain-gauge load cell to improve the
dynamic response of the instrument. Supramaximal electrical stimuli were
used to evoke a maximal tetanic response from the triceps surae and ensure
constant muscle activation at each angular velocity studied. Angle-specific
torques were measured over a range (0.5-5.0 rad/s) of preset velocities,
torque decreasing in a nonlinear manner with increasing angular velocity.
The torque-velocity data was adequately described by an exponential
equation of the form: V = a(e-1/b - e-Po/b) where V = velocity (rad/s), P =
torque (N.m), Po = isometric torque (N.m), and a and b are constants. The
mean intrasubject coefficient of variation of torque over the range of
velocities studies was 7.9 +/- 1.88% (SD).
