Ligamentous separation force in rats as influenced by training, detraining, and cage restriction¹

Abstract

This experiment was divided into two 8-week phases in order to determine the effects of various combinations of cage restriction, spontaneous running, swim training, and detraining on the force required to separate the medial collateral knee ligament from its bony attachment site in male Wistar rats. Training consisted of swimming in a tank for 15 minutes per day, 5 days per week, with 2 percent body weight attached as an overload. Spontaneous running was provided by permitting some animals to run in exercise wheels attached to their cages. Animals were sacrificed after 8 weeks (N=37) and at the conclusion of the 16-week experiment (N=56). Statistical analysis of the data indicated that ligamentous separation force was enhanced by physical activity, but detraining did not appear to alter the ligamentous separation force gains which had been acquired through training.