Based on the physiological principles of the muscular force-velocity concept, this
paper deals with the special problems associated with determining and interpreting
force-velocity relations of muscles in situ particularly in humans. In the strict
sense, instead of force-velocity relations merely torque-angular velocity relations
of a Joint can be measured directly under in situ conditions. This calls for biomechanical
model calculations to obtain force-velocity relations of Single muscles involved in
Joint motions. In addition to discussing these basic principles, the methodological
problems arising in measurements with so-called isokinetic dynamometers are also explicitly
described. An important message of this paper is to sensitize potential users of this
method to these problems as the isokinetic dynamometry has more or less become Standard
procedure worldwide. The possibility of the characterization of muscle fiber composition
and the evaluation of power on the basis of human muscle force-velocity relations
is also discussed. A final section considers the effects of muscle training on the
torque-angular velocity relations. The Contents of this paper can be understood as
a guide to avoid obtaining conflicting results when measuring human torque-velocity
relations.
Human muscle - force-velocity relation - torque-velocity relation - Hill's equation
- isokinetic dynamometry - concentric contraction - eccentric contraction - power
- muscle fiber type
