Fig. 6. The effects of temperature on stretch-induced enhancement of twitch force in indirectly stimulated muscle. Twitch forces are expressed as values relative to the force obtained by direct stimulation at one muscle length (l₀). The thick line is the same regression curve as shown in Fig. 5A. Forces were measured 2 min after stretching each preparation from l₀ to the length indicated on the abscissa at three different temperatures; open circles, 4°C (N=5); filled triangles, 12°C (N=4); open squares, 22°C (N=4). All animals had been kept for more than 2 months at room temperature before the experiment.