A pre workout supplement helps to increase your energy and motivation to train through the combination of numerous energy promoting ingredients. They can be very useful on days where you really need to train but simply don’t feel like you have the energy, a lot of pre workouts include caffeine, beta alanine and other nitric oxide and other energy promoting ingredients. Increasing the stimulus to train helps to achieve a greater commitment and work rate, it is true often a trainer has this drive without the need for a pre workout but on the days where you don’t they can be very useful.