Gregg Valentino is one of the most controversial, yet popular bodybuilding icons, and is considered by some as the biggest bodybuilder ever. He holds the record for the biggest biceps in the world at 28". He started bodybuilding at the age of 13 and after over 23 years of training naturally, Gregg decided to experiment with steroids (and some say he's injecting Synthol). During this time, his arms grew from an impressive 100% natural 21" to an inhuman 28". After years of steroids injections, his body finally fought back—his bicep "exploded.” He eventually went to jail for steroid possession and is now rebuilding his life.
The most commonly used AAS in medicine are testosterone and its various esters (but most commonly testosterone undecanoate , testosterone enanthate , testosterone cypionate , and testosterone propionate ),  nandrolone esters (most commonly nandrolone decanoate and nandrolone phenylpropionate ), stanozolol , and metandienone (methandrostenolone).  Others also available and used commonly but to a lesser extent include methyltestosterone , oxandrolone , mesterolone , and oxymetholone , as well as drostanolone propionate , metenolone (methylandrostenolone), and fluoxymesterone .  Dihydrotestosterone (DHT; androstanolone, stanolone) and its esters are also notable, although they are not widely used in medicine.  Boldenone undecylenate and trenbolone acetate are used in veterinary medicine .