Figure 1. Superposed force and sarcomere length records for a chemically permeabilized rabbit psoas fiber.

The fiber was subjected to a ramp stretch followed by a ramp shortening in 4 different pCa solutions. Force rises more quickly during the latter stages of the stretch when the fiber is activated. The records in the pCa 9.0 and pCa 4.5 solutions are re-plotted from Fig 4 of Campbell & Moss [7].