Well, I'm sure you have thought of ephedra products or a simple cup of coffee. Sometimes when feeling very run down after a long day it may be due to not getting enough water. Personally I like a very complex carb thirty minutes before a workout. Yams, brown rice, oatmeal ect... If not cutting try this I love it when not dieting. All natural peanut butter, a lot, on hearty whole wheat with honey. This is a sure pick-me-up that will last through your workout.