For the off-season athlete there is no anabolic steroid more important or beneficial than testosterone. High levels of testosterone will promote significant increases in lean muscle mass and strength. This is assuming that the individual is consuming adequate calories. Compounds like Testosterone Propionate are not magical, you will still need to feed your body enough calories. During an off-season period of growth, this means total caloric intake will need to be slightly above maintenance. This will, unfortunately, promote body fat gain. However, the key to a successful off-season is gaining lean tissue while minimizing body fat gain to the fullest extent possible. By supplementing with Testosterone Propionate you will be able to achieve this more efficiently. High testosterone levels will promote a stronger metabolic rate. This is not a license to eat like there’s no end in sight, but you should be able to make better use of your calories.
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 . 
At least one studio made a conscious effort to keep its leading man squeaky clean. Before Cavill began his grueling five-month preproduction training for Steel , Warner Bros. requested a list of exactly what the training team might ask Cavill to use. Twight gladly complied, given that he believes radical body recomposition can be done naturally when it is guided by experienced trainers and driven by discipline and commitment. For Cavill, Twight recommended only Udo's Oil (a blend of essential fatty acids) and magnesium to aid sleep, the time when growth hormone occurs naturally.