Effect of exercise, immobilization and intermittent stretching on strength of knee ligaments of albino rats

Sixty male albino rats were divided into four groups. The rats in the first group were exercised; those in the second were subjected to intermittent passive stretching of one hind leg; those in the third group had one hind leg immobilized; those in the fourth group served as controls. At the end of 4 weeks, all animals were sacrificed and the muscle tissue was dissected from the hind legs. The limbs were then torn apart at the knee joint. No significant differences were found in the amount of stress required to tear the knee ligaments in the various groups.