Figure 4.

Exploring alternative feedback mechanisms. Contours representing the matching conditions ${\beta }_0^{\text{effective}}/{\beta }_0^{\text{Land}}=1$ (solid curves) and ${\beta }_1^{\text{effective}}/{\beta }_1^{\text{Land}}=1$ (dotted curves) are plotted, based on the different hypothetical feedback scenarios: (a) total force, (b) active force only, (c) passive force only, and (d) sarcomere strain $C=\text{SL}/{\text{SL}}_0-1$ (Eqs. 8, 9, and 10). Plots (e)–(h) show the length dependences of $F_{\max }$ corresponding to the colored markers in (a)–(d), respectively. To see this figure in color, go online.