A balanced diet for healthy runners should include these essentials: carbohydrates, protein, fats, vitamins, and minerals. Here are some basic guidelines for a nutritious, healthy balance:
As a runner, carbohydrates should make up about 60 - 65% of your total calorie intake. Without a doubt, carbs are the best source of energy for athletes. Research has shown that for both quick and long-lasting energy, our bodies work more efficiently with carbs than they do with proteins or fats. Whole grain pasta, steamed or boiled rice, potatoes, fruits, starchy vegetables, and whole grain breads are good carb sources.
Protein is used for some energy and to repair tissue damaged during training. In addition to being an essential nutrient, protein keeps you feeling full longer, which helps if you're trying to lose weight. Protein should make up about 15% - 20% of your daily intake. Runners, especially those running long distances, should consume .5 to .75 grams of protein per pound of body weight. Try to concentrate on protein sources that are low in fat and cholesterol such as lean meats, fish, low-fat dairy products, poultry, whole grains, and beans.
More: Sports Nutrition Mistake: Not Getting Enough Protein
A high fat diet can quickly pack on the pounds, so try to make sure that no more than 20 - 25% of your total diet comes from fats. Stick to foods low in saturated fats and cholesterol. Foods such as nuts, oils, and cold-water fish provide essential fats called omega-3s, which are vital for good health and can help prevent certain diseases. Most experts recommend getting about 3,000 mg of omega-3 fat a day.
Runners don't get energy from vitamins, but they are still an important part of their diet. Exercise may produce compounds called free radicals, which can damage cells. Vitamins C, E, and A are antioxidants and can neutralize free radicals. Getting your vitamins from whole foods is preferable to supplementation; there's no strong evidence that taking supplements improves either health or athletic performance.
Calcium: A calcium-rich diet is essential for runners to prevent osteoporosis and stress fractures. Good sources of calcium include low-fat dairy products, calcium-fortified juices, dark leafy vegetables, beans, and eggs. Your goal should be 1,000 to 1,300 mg of calcium per day.
Iron: You need this nutrient to deliver oxygen to your cells. If you have an iron-poor diet, you'll feel weak and fatigued, especially when you run. Men should aim for 8 mg of iron a day, and women need 18 mg. Good natural sources of iron include lean meats, leafy green vegetables, nuts, shrimp, and scallops.
More: Sports Nutrition Mistake: Not Getting Enough Iron
Sodium and other electrolytes: Small amounts of sodium and other electrolytes are lost through sweat during exercise. Usually, electrolytes are replaced if you follow a balanced diet. But if you find yourself craving salty foods, it may be your body's way of telling you to get more sodium. Try drinking a sports drink or eating some pretzels after exercise. If you're running longer than 90 minutes, then you should need to replace some of the electrolytes you're losing through sweat by drinking sports drinks or taking in salt during your runs.
Nutrition is highly individualized and often times the general rule of thumb is, “If it tastes OK in training, chances are it won’t work in a race. If it tastes great in training, it might work in a race.” Because racing situations greatly magnify and change the taste of all food and drink, it is important to remember that the best source of calories and fluid for a race comes from those that you can get down and keep down. Most of the time, fluids or gels are usually a better choice than solid foods.
Depending on the length of your race and the environmental conditions, you may or may not need as much fuel. Water can be used in race situations of 45 minutes or less (as long as you fueled up prior to the race) while sports drinks or easy-to-digest foods, liquids or gels should be used thereafter. Carbohydrates, fluid and sodium are the most important nutrients during competition and should be an integral part of your race nutrition plan.
I know it’s tough to try to choke down something on race morning but you need to get some carbohydrate in your body because you are coming off of an overnight fast and internal glycogen stores are used as you sleep. Eat 2-4 grams of carbohydrate (8-16 calories) per kilogram of body weight 2-4 hours before the start of the race and drink about 20 ounces of sports drink during this time also. Sip on around 10 ounces of a sports drink 10-20 minutes prior to the start.
During the Race
Since athletes absorb different amounts of calories per hour, it is important to experiment with quantity during training. In general, for shorter races, consume 30-60 grams of carbohydrate (120-240 calories) per hour. For longer races (more than 8 hours), you may be able to experiment with up to 90 grams (360 calories) per hour.
Because fluid empties from the stomach very differently from athlete to athlete, experiment with fluid quantities during training also. In general, drink 1-2 bottles of fluid per hour (including carbohydrate and sodium) and divide this into about 3-8 big sips/gulps every 15-20 minutes.
After the Race
The key nutrition components to consume within 30-60 minutes (the sooner the better) after a race are fluid, carbohydrate, protein and electrolytes. Check the labels on your favorite products and food to meet the following criteria.
Fill up your fluid and carbohydrate “tanks” post-race by drinking about one bottle of sports drink for every pound of body weight that you lose and eat about 50-100 grams (200-400 calories) of carbohydrate. This can come in the form of liquid, solid or gel, whichever you prefer.
For protein, it is good to eat from 10-20 grams (40-80 calories) to help speed recovery along with at least 500-700 milligrams of sodium. Try to keep the fat intake very low if consumed at all in this window directly after a race.
After this initial post-race feeding, you can sit back and enjoy without worry that your recovery process will be enhanced. Reward yourself with a mixed meal made up of carbohydrate, protein and fat about 2 hours after you finish and keep drinking those fluids for the next few hours to re-hydrate your body.
Remember, a well-planned nutrition program may mean the difference of setting a new PR, a win, finishing, or simply feeling good at the finish. Don’t overlook your nutrition training for your race. Plan ahead and try it in your training under race simulation conditions first.
Article take from: http://running.about.com/od/nutritionandhydration/a/runnersdiet.htm and http://runnerscorner.com/articles/racenutrition/