Every time we come across those heavily built and muscular athletes a question pops in to our minds, is it genuine or artificial? Steroids, or exogenously administered testosterone shots (T-shots) are used for several indications, and whether used for medical purposes or as recreational performance-enhancing drugs (Muscle building and repair) they have profound impact on male fertility. Indications make no difference when it comes to T-shot effects on male reproduction, they may render the male infertile. By the time a testosterone shot is administered, brain glands recognize it immediately; however it lacks the capacity to identify its source, whether it being from the testes (Endogenous) or simply an injection (Exogenous T-shot). As described previously, the brain glands act through the feedback mechanism, same as the fridge thermostat, so after receiving T-shots, the brain glands will immediately shut down all gonadotropins (GN’s) to the testes namely the LH and FSH (Being tricked thinking that this massive testosterone levels are coming from the testes), however, this will ultimately result in a marked reduction in the natural testosterone secretion from the testis (Endogenous) and eventually arrest in sperm production.