Effect of intermittent stretch on immobilised muscle

When muscle is immobilised in a shortened position there is a reduction in fibre length and an increase in the proportion of connective tissue. This results in reduced muscle compliance and a loss of range of joint motion. Experiments have been carried out to determine whether short periods of stretch are effective in preventing these changes. The soleus muscle of the mouse was immobilised in a shortened position for a period of 10 days by means of a plaster cast. Every two days the cast was removed and the muscle passively stretched for a 15 minute period. It was found that this treatment prevented the connective tissue changes but did not prevent the reduction in muscle fibre length, which in itself resulted in considerable loss of range of motion.