When you talk about legal steroids the subject of prohormones is sure to come up. Prohormones are precursors to parent hormones such as testosterone, nor-testosterone, nandrolone. These hormones are converted to parent hormones via liver enzymes. Prohormones are used mainly by athletes looking to increase size, strength, endurance, reduce recovery time or add lean body mass. They are most often used for increasing muscle mass or reducing body fat levels.

Pro-hormones, and/or Pro-steroids (I won't get into all the subdivisions and categories since there are many and they all work more similarly than you're led to believe) are essentially weak steroids. Many of them were once legal, but are now gone. No doubt about it, they worked, not as well as pharmaceutical grade steroids, but better than most nutritional supplements. Pro-hormones are precursors of certain natural or synthetic anabolic androgenic steroids (AAS). They are often referred to as legal steroid alternatives to AAS.

Prohormones can have the same side effects as anabolic steroids, and are dependent upon the user as to which side effects one might experience. Some side effects are acne, hair loss, breast tissue enlargement, and prostate swelling. Prohormones are substances that are enzymatically converted to anabolic hormones in the body. They are differentiated from anabolic steroids in that enzyme conversion is a rate limiting factor in how strong of a response they illicit.

Oral delivery is the easiest but is usually associated with the lowest bioavailability and a higher possibility of liver toxicity. Also, oral use necessitates dosing 3-4 times daily as it only keeps blood levels elevated for a few hours. Oral steroids have a 17aMethyl group which blocks liver enzymes and therefore can cause liver enzymes to increase. Often grey market anabolic steroids like the prohormones (ones not classified by the DEA, yet not legal by FDA standards) use this 17a Methyl delivery system to increase potency.

Prohormones and even the legal steroids cannot be taken year round, but are rather run in short "cycles" by bodybuilders and other athletes. This is especially true of the oral steroids because of their effect on the liver and liver enzymes.

Cycling is assumed to have three purposes: to optimize results in a given training phase; to prevent harmful side effects by giving the body a rest; and to overcome the body's tolerance for the supplements. Typical supplementation cycles run between four and 12 weeks. Finally, it is especially important to take adequate time off after each cycle with these prohormones or legal steroids to allow the body to recover and to follow a proper post cycle therapy.