Anabolic steroids are synthetic versions of testosterone, the body’s natural sex hormone. They assist athletes by facilitating efforts to gain strength and muscle mass for increased muscular endurance, power and speed.

Male hormones such as testosterone and its metabolite di-hydrotestosterone are responsible for the developmental changes that occur within the male body through adolescence. Steroids possess both androgenic and anabolic properties. Some of the androgenic effects include changes in sexual characteristics such as shrinking of the testicles, hair growth on the body and face, hair loss on the scalp, and increased aggressiveness. Athletes are primarily concerned with the anabolic characteristics of steroids including accelerated development of the muscles, connective tissues, bones, and red blood cells.

Function & Processes

Steroids were originally developed to treat specific medical conditions in which the above anabolic benefits would directly aid patient recovery. Although they function in different ways, the primarily method involves receptor stimulation within muscle cells which in turn activates specific genes. This is known as a “genomic effect” or “direct effect” as it involves the process known as gene transcription. Evidence of the direct or genomic effects, as well as indirect or non-genomic effects of anabolic steroids have been observed in virtually every examined form of tissue in the human body. When a steroid is consumed either orally or via injection, it travels to the androgen receptors located within the various cells. As illustrated below in Figure 1, this connection activates the hormone receptor creating a messenger RNA (mRNA), which signals the DNA to construct specific proteins. These proteins travel throughout the body eliciting the aforementioned anabolic/growth responses. Although anabolism is the primary action of steroids, they also elicit many other desirable and undesirable effects.

Figure 1.


Steroidal Effects

Though the stimulus provided during weight training is necessary for maximum muscle development, steroids possess the inherent ability to build muscle with or without such training.

By increasing the user’s endurance, they help athletes train much harder, for longer periods of time, and accelerate muscle recovery. This allows the athlete to make continued progress at a rate far beyond normal capacity.
 
Because anabolic steroids are derivatives of the male hormone testosterone, their use potentially decreases natural testosterone secretion. Once the body senses and registers the presence of steroids, it responds by ceasing natural testosterone production. Similarly, discontinuation of steroid use causes the body to re-initiate its own production of testosterone.  However, there is a significant delay between these events, during which steroid abusers tend to rapidly lose strength and size.  At this time many employ ancillary products to bridge this gap and retain gains.