The Original Performance Energy Bar. Fuel for optimum performance. PowerBar® is America's original energy bar fueling more world class athletes to records and championships than any other energy bar. Carbs for energy. Staying energized is essential to athletic performance. Carbohydrates have long been known as the body’s most efficient source of fuel. In fact, athletes require 60%-70% of calories from carbohydrates to get the energy required for consistent training and competition. Unfortunately, the body’s capacity to store this all-important fuel is relatively small. That’s why PowerBar contains 45g of carbohydrates to refuel working muscle and keep you going. Vitamins for energy production. Did you know that in order to process food into usable energy, your body needs B-vitamins? B-vitamins are vital to energy production. And since B-vitamins work best as a team, PowerBar combined 100% DV of all the energy related B-vitamins. Protein for muscle repair. Exercise can breakdown muscle tissue. As an athlete, your body requires more protein to help build and repair muscle tissue that can be damaged during activity. PowerBar contains milk protein, a complete protein that contains all the essential amino acids required by your body to build muscle.