A three‐dimensional muscle model: A quantified relation between form and function of skeletal muscles

A three‐dimensional muscle model with complex geometry is described and tested against experimental data. Using this model, several muscles were constructed. These muscles have equal optimum length but differ in architecture. The force exerted by the constructed muscles, in relation to their actual length and velocity of shortening, is discussed. Generally speaking, the constructed muscles with considerable pennation have great fiber angles, a great physiological cross section, a narrow active and steep passive length‐force relation, and a low maximal velocity of shortening. The maximal power (force times velocity) delivered by the constructed muscles is shown to be almost independent of the architecture of the muscles. The steepness of the passive length‐force relation is determined mainly by the shortest fibers within the group of constructed muscles, wheras maximal velocity of shortening and the width of the active length‐force relation are determined mainly by the longest fibers.

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