The effect of exercise and anabolic steroids on the mechanical properties and crimp morphology of the rat tendon

Abstract

The administration of anabolic steroids is believed to be widespread among athletes, but convincing evi dence relating to the beneficial effect of such com pounds on collagenous structures of the locomotor system is not available. Since it has not been possible to analyze relevant human tissue, an animal model was used to investigate the change in particular mechanical and morphological properties of rat tendon after a period of controlled exercise, with or without anabolic steroid supplementation. A significant difference (P < 0.001) was found between the crimp angles and lengths of collagen fibrils and theoretical toe limit strains of the four groups under study. No other significant differ ences (P > 0.05) were observed. Controlled exercise and anabolic steroid administration produced the great est change in crimp parameters and the largest theo retical toe limit strain. This implies that muscle contrac tion will be greater for a given stress and thus alter the normal biomechanics of limb movement. Further stud ies are required to determine more definitively the ef fects of anabolic steroids on a connective tissue such as tendon.