824068.fig.001a
(a)
824068.fig.001b
(b)
824068.fig.001c
(c)
Figure 1: Representative model-predicted force response to chirp-length perturbation for a control-rat fiber (i.e., cTnCWT fiber). (a) Total force response that includes force components due to low-frequency XB recruitment component, 𝐸 0 𝜂 ( 𝑡 ) , and high-frequency XB distortion component, 𝐸 𝑥 ( 𝑡 ) . (b) Force response due to low-frequency XB recruitment component, 𝐸 0 𝜂 ( 𝑡 ) . (c) Force response due to high-frequency XB distortion component, 𝐸 𝑥 ( 𝑡 ) . 𝐸 0 and 𝐸 represent stiffness magnitudes that scale the contributions of recruitment and distortion components to total stiffness. 𝜂 ( 𝑡 ) and 𝑥 ( 𝑡 ) are variables that describe the dynamic changes in the XB recruitment and distortion components due to changes in muscle length. Two chirps were administered to emphasize low- and high-frequency components of the force response: from 0.1 to 4 Hz over 40 s in chirp 1 and from 1 to 40 Hz over 5 s in chirp 2.