Long-Term changes in human skeletal muscles after anabolic steroid administration
Description du projet
The use of anabolic androgenic steroids (AAS) is widespread within both competitive and recreational sports in which large, strong muscles are an advantage or the primary goal (bodybuilding). To build more muscle mass and to enhance muscle force and power, AAS are particularly effective. In this study, we want to investigate the long-term effects in the skeletal muscles that in particular are related to nuclei of the muscle fibers. Because the nucleus of a cell controls the different cellular-processes, including adaptations to training, long-term or irreversible changes in the number of nuclei in a muscle fiber will potentially give a person using AAS an advantage also after he/she stops using the drugs. Athletes caught as drug users are quarantined for at most 2 years for a first time offence, however, this should be reevaluated if the effects of AAS are shown to last many years after the athlete stops using the drugs. These research aims for a human study are directly derived from a recent animal study conducted by some of the co-investigators in this application. In this human study we will recruit males (20-40 years) with no strength training experience. The volunteers will be administrated a testosterone preparation or placebo (saline) by intramuscular injections during a 3 month period. Concomitantly they will follow a heavy strength training program. After the initial 3 months the participants will refrain from strength training for 9 months, but then re-train their muscle for 3 months without any drugs. Muscle tissue samples, measures of muscle mass and strength will be collected and assessed before and after each period. The main question is if the volunteers that received testosterone during the initial 3 months will re-build their muscle faster than the participants that received placebo.
The use of anabolic steroids has in an animal study been shown to give
long-term effects in skeletal muscle, by adding nuclei (DNA) to the muscle fibres and accelerating re-training. This means that the advantage of anabolic steroid use may be present in years after the athlete has stopped using the drugs. This study aims to test the hypothesis that the results from this animal study applies for humans.