Specifications

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The figure above is a schematic representation of the muscle model. We can get a complete impression of
the parameters of the model if we pick the model from the Class List as we have done before and insert a
template into our AnyScript model:
AnyMuscleModel2ELin Model2 = {
F0 = 200;
Lfbar = 0.3;
Lt0 = 0.3;
Epsilonbar = 0.05;
V0 = -0.3;
};
AnyMuscleModel3E <ObjectName> = {
F0 = 0;
Lfbar = 0;
Gammabar = 0;
Epsilonbar = 0;
Lt0 = 0;
Fcfast = 0;
//Jt = 3;
//Jpe = 3;
//K1 = 2;
//K2 = 8;
//PEFactor = 5;
};
Several of these elements are described already in the two-element model above, but some are new and
described in the table below. No excuse we can make is going to soften the fact that muscle modeling at this
level of detail is a technical matter, and it is not possible to describe the physiological and mathematical
background in detail. Instead please refer to the publications at the end of this lesson for further
information:
Gammabar Gamma is the so-called pennation angle. It reflects that fact that most muscles have the
fibers misaligned with the directions of action of the muscle. Gamma changes when the
muscle extends or contracts, and Gammabar is the value of Gamma in the muscle's neutral
position. It is possible to find values for Gammabar for most major muscles in the human
body in the anatomical literature. Gammabar is measured in radians.
Fcfast Muscle fibers come in two flavors: fast twitch and slow twitch, and the composition of these
vary between the muscles as well as between individuals. Fast fibers, as the name indicates,
have the ability of fast action at the cost of stamina, and slow fibers have opposite properties.
Sprint runners have a high proportion of fast twitch muscles while marathon runners have
many slow twitch muscles.
Fcfast is the fraction of fast twitch fibers in the muscle. It is a fraction between 0 and 1 and