XPI Syntheroid is a nutritional supplementation program that claims that it can increase strength, mass, and sexual vigor by boosting men’s testosterone function. They say that it can improve the raw amount of testosterone that men produce, the potency of that testosterone’s effects, as well as preventing the conversion of testosterone into estrogen.
Their promotional materials state that the combination of all these effects can lead to boosts in men’s ability to generate new muscle tissue, as well as helping to repair damaged existing tissues, and that it can help increase the rate with which men’s bodies burn fat. Sexually, it can help to boost men’s sex drive, increase the quantity and quality of their seminal production, and improve the intensity of their orgasms.