Average Dose: 300 - 500mg per week
Half Life: 2 - 3 days
Water Retention: No
Aromatization: No
DHT Conversion: No

GP MAST 100 (dromostanolone propionate), is a popular steroid among competitive bodybuilders. It is commonly used in contest preparation for many reasons. To begin with, dromostanolone propionate is a derivative of DHT (dihydrotestosterone), and therefore, it will not aromatize into estrogen. Competing bodybuilders find this extremely beneficial because aromatization typically causes excess water retention which may give the muscles a smooth appearance. Another advantage of GP MAST 100 is its strong androgenic component. The androgenic effect of this steroid can cause a noticeable improvement in muscle density and hardness which can help the bodybuilder obtain the "ripped" look if his bodyfat percentage is low enough. The androgenic effect is also crucial because it helps to provide sufficient "kick" or "drive" for intense training when an athlete has lowered his caloric intake for contest preparation.

GP MAST 100 can also be used successfully by bodybuilders preparing for a drug-tested show. The substance dromostanolone propionate is fast acting and quickly broken down. The athlete can therefore use GP MAST 100 up to about ten days before a drug test. The average dosage of GP MAST 100 is 100 mg injected every other day. It is best to inject GP MAST 100 every 2-3 days because it has a short duration of effect. Popular steroids stacked with MAST 100 include GP Tren Hex 100 (Trenbolone Hexahydrobenzylcarbonate), GP Stan 50 Inj (Stanozolol), and GP Oxan (Oxandrolone). Athletes rarely experience any side effects with this steroid. GP MAST 100 is not hepatoxic, and gynecomastia should not be a concern since it does not convert into estrogen. Some possible side effects include acne, accelerated hair loss, and increased aggression. The main disadvantage of GP MAST 100 is its very poor availability on the black market and its high price.