When it comes to building muscle strength it requires adequate total calorie intake based on the proper combination of calories from carbohydrates, protein, and fat. Energy bars and sports drinks may be used to supplement calorie intake when engaged in more rigorous strength building.

Total Calories
Calories are very important to allow the body the ability to build strength and lean body mass. If your body is deprived of adequate calories then lean mass will be used for energy. In order to get the proper amount of calories to maintain body weight you can figure that an average sedentary person needs 8-12 calories per pound of body weight. Any additional calories burned as a result of exercise can be added to the maintenance number.

Carbohydrate
Carbohydrate is the predominant energy source for strength training. They are stored as glycogen in the muscles, it is the fuel used to supply energy for short, intense bursts of power. The harder and longer you work out, the more glycogen your muscles require. Once these stores of glycogen are gone your energy level will drop and you will run out of fuel to power muscle contractions. The recommendation for carbohydrates is 55% of your total calories per day from carbohydrate. Remember to choose high fiber, complex carbohydrates such as whole wheat pasta, brown rice, and whole wheat bread.

Protein
Protein is the basic building material for muscle tissue, and those who do strength training need more than the non-exercisers. However, most strength athletes still overestimate their protein needs. Daily protein recommendations for serious strength athletes are 1.2-1.4 grams/kg per day. That's about 90 grams of protein/day for the 140-pound athlete. An ounce of meat offers 8 grams of protein and most dairy foods offer 8 grams of protein per cup.

Fat
After you've met your carbohydrate and protein needs there is room for fat. Fat is an essential nutrient, however, you require a small amount of it to remain healthy. Less than 30% of your total daily calories should come from unsaturated fat.

Energy bars and sports drinks
Energy bars and sports drinks may be helpful if exercise lasts longer than 1 hour. Carbohydrate supplements can be useful to help fit adequate carbohydrates into a busy day if you don't have time to eat a meal. Consuming a meal-replacement beverage just after muscle-building exercise is easy to do, but you can do the same thing with a peanut butter sandwich, yogurt and fruit, or other foods. It is important to consume some protein and carbohydrate within the hour after the workout in order to fuel muscle growth and replenish energy stores for your next workout. Be careful with the calories from bars and recovery drinks--it can be easy to overdo the calories after the workout. The best option is to choose protein bars with less than 220 calories and a minimum of 10 grams of protein per serving.