Because football is one of the most grueling, calorie-consuming sports, proper nutrition is crucial to optimal athletic performance. Intensive preseason training, with two-a-day practices in brutal heat, require refueling the body with the highest-quality foods and plenty of fluids to replenish lost minerals. Key food groups to improve speed, stamina and strength include protein, carbohydrates and fruits and vegetables. Because of the potential for injuries, bone-building foods are also advised.

Protein provides the building blocks that maintain the muscles, bones, body organs and blood. Protein can come from both animal and vegetable sources, including fish, meat, chicken, eggs, dairy products, nuts, seeds, legumes and lentils, the KidsHealth website advises. After playing football, players may need protein foods with higher fat content — steak, salmon, roast beef and hamburgers, for example. Salmon, with its high content of tissue-repairing omega-3 fatty acids, is a strong choice for a post-game meal.

Writing for the Training & Conditioning website, Lesli Bonci, director of sports nutrition at the University of Pittsburgh Medical Center, explains since football requires short bursts of energy followed by periods of rest, carbohydrates are a key food requirement. Quality complex carbohydrates include foods such as oatmeal, brown rice, whole-grain breads and pastas, potatoes and corn. Eating carbohydrates in their unrefined state provides more of the vitamins and minerals lost during the refining process. Instead of high-fat French fries with your post-football steak, try a baked potato with a sliver of butter.

Because football takes a great toll on the body, protecting the body by eating bone-building foods is a wise idea. Joy Bauer, a registered dietitian who serves as the nutrition expert for NBC-TV's "Today" show, lists on her website some key bone-building vitamins and minerals and their food sources: calcium, from yogurt, cheese and almonds; vitamin D, from eggs, milk and fortified cereals; magnesium, from pumpkin seeds, quinoa and brown rice; potassium, from bananas and cantaloupe; vitamin K, from green leafy vegetables; and vitamin C, from strawberries, bell peppers and broccoli. While eating these foods do not guarantee you won't suffer an injury, football players should take every opportunity to guard against injury.

Football players burn off an immense number of calories during practices and games. Bonci recommends players consume three meals a day along with snacks before and after practices and games. Each meal should look like a peace sign, with one-third of the plate devoted to protein, one-third to complex carbohydrates and one-third to fruits and vegetables. A snack or meal should also be consumed 30 minutes after activity for the best benefit.