To be ready for today's and tomorrow's work out you need to eat well. Your muscles use and store energy from glucose. Foods that supply glucose are carbohydrates. Choose nutritious carbohydrate foods such as fruits, grains, starchy vegetables, milk, and yogurt.
Go into a work out well fueled by eating a good meal a few hours before or snack an hour or so before. Within 2 hours of working out, plan to eat a meal. If it's not meal time, eat a piece of fruit or drink a glass of milk.
Be well fueled and have a great work out!