Prohormones are chemical compounds that work as precursors of a particular hormone when they are consumed, converting into that hormone within the body thanks to the interaction of enzymes. By taking prohormones, you give your body with elements it needs to create the hormones faster. Bodybuilders use prohormones which convert into anabolic (growth) hormones.
Boosted levels of testosterone are going to help you increase your muscle mass and strength, as well as optimising fat loss. Stacking prohormones with other compounds such as SARMs creates a synergistic effect and increases your potential within a short space of time. Stacking is only recommended for experienced users.
As with all hormonal compounds, there is the chance of increasing the natural effect of those hormones. This means with boosted testosterone there is the risk of increased aggression, loss of hair, skin irritation and poor skin generally including acne and loss of sleep. There is also the chance of some of the more positive attributes associated with increased levels of testosterone like a higher sex drive and improved appetite.