TestoFuel is a supplement that increases testosterone, that is, it is designed to break the muscle growth barrier and make that leap that you have always sought. I got to know testofuel when looking for a supplement to increase testosterone. In this search, I got to know testofuel through hundreds of people who train and who are having incredible results. Testofuel is designed to trigger testosterone production in your body in a completely natural way. This increase in testosterone is accompanied by an increase in muscle mass.