THE EFFECT OF ANABOLIC-STEROIDS ON THE BIOMECHANICAL AND HISTOLOGICAL PROPERTIES OF RAT TENDON

Twenty-four male rats were divided into four groups, with anabolic steroids and exercise as variables. Biomechanical tests and histological evaluations were performed. The results of the biomechanical tests suggested that anabolic steroids produce a stiffer tendon, which fails with less elongation. The energy at the time when the tendon failed, the toe-limit elongation, and the elongation at the time of the first failure were all affected significantly. Changes in the force at failure were not statistically significant. No alterations of structure were noted when the specimens were viewed with light microscopy. Alterations of the sizes of the collagen fibrils were noted on electron microscopy. CLINICAL RELEVANCE: Anabolic steroids are used commonly by athletes to enhance performance in sports activities in which a premium is placed on strength and power. It appears that anabolic steroids have detrimental effects on the muscle-tendon unit in addition to potentially serious systemic side effects. Therefore, athletes who use anabolic steroids place the muscle-tendon unit in double jeopardy of failure. Muscular strength is increased, but the tendon becomes stiffer and absorbs less energy, so it is more likely to fail during certain activities.