The contractile properties of adult rat soleus were evaluated in response to an “isometric
type” and a repetitive isotonic weight lifting exercise. After 6 weeks of training,
the maximum twitch (Pt) and tetanic (PO) tension and contraction times (CT) were compared in the control and exercised groups.
The data revealed a nonspecific potentiation of Pt in the exercised groups without
any change in the PO. The repetitive isotonic weight lifting significantly prolonged the CT of the muscle,
which suggests that the stimulus of this exercise may induce a physiologic “slowing”
in the muscle via alterations of the sarcoplasmic reticular system.
contraction time - exercise - muscle - twitch - tetanic tension
