To get the maximum pump and the most reps from your workout, a high level of energy is needed. A pre workout energy supplement is designed to provide you with the energy to get into the gym and get the most out of it. The supplements range in ingredients, with different additives to enhance the workout further, so that it can be tailored to your personal body building goal. The pre workout energy supplements not only provide energy, but often also provide your body with an alternate source for the proteins and other components needed to build muscle instead of leaching the muscles you have worked so hard to build.