Computer simulation of accelerated contractions of six muscle models with the same overall mass (6.5 g), maximum isometric force (30 N), optimal length (0.015 m), and maximum contraction velocity (0.15 m/s). The muscles were fixed at one end and always fully active (*q* = 1). Models differ just with respect to the number of accelerated discrete point masses approximating a continuous distribution of muscle mass. The point masses were connected by an equal number *I*_{M} (see insets in ) of contractile elements. Their respective optimal lengths *l*_{CE,opt,i} were chosen equal to the optimal muscle length *l*_{M,opt} divided by *I*_{M}. The graph depicts the velocity of the point mass at the free end (a), the force at the fixed end (b), and the effective mass (c), that is, the ratio of force at the fixed end and acceleration of the point mass at the free end, versus time. The effective mass to be expected for an exactly linear acceleration distribution along the muscle would be half of the muscle mass (Mass_{M } = *ℳ*; (): *μ*_{eff} = *ℳ*/2 = 3.25 g). The analytic solution for one CE accelerating one point mass predicts (see ) a typical time of 3.6 · 10^{−4} s for this muscle to approach *v*_{max}.

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