Figure 1.

Electrically-evoked isometric contractions of the triceps surae were recorded in situ in semistarved and refed rats and in their respective controls. Force characteristics and kinetics of contraction and relaxation were determined. (A) The average phasic traces of refed rats and their controls are depicted, illustrating muscle contraction followed by complete relaxation. The kinetics values (time to peak and time for half-relaxation from the peak) are highlighted in green (control) and in red (refed). (B) Absolute phasic and tetanic tensions, (C) specific phasic and tetanic tensions, (D) kinetics of contraction and relaxation, (E) force-frequency relationships, and (F) muscle fatigue were determined as described in the text. SS, semistarved rats; C_SS, control of semistarved rats; RF, refed rats; C_RF, control of refed rats. n = 8–10; Mann-Whitney test; ^*P ≤ 0.05; ^**P ≤ 0.01; ^***P ≤ 0.001; ^ns, not significant, comparing SS or RF to their respective control.