Runner's Caloric Intake

Running for exercise isn't a license to eat whatever you want, whenever you want. Successful runners use nutrition tips for runners to optimize their performance, whether in training or getting ready for a race.

When you're training for a race, you need to consider your eating habits while training and apply those to your races. There's some wiggle room when it goes to calculating total calories for a runner.

How many calories you burn depends on how fast you run, how much you weigh and your metabolism. According to Harvard Health, a 125-pound person running 3 miles at a 10-minute-per-mile pace will burn about 300 calories. A 155-pound person running 10 minutes per mile will burn about 372 calories on that same 3-mile run. A 185-pound person running the same pace will burn about 444 calories.

You can figure out where your own weight is on that spectrum, and your approximate pace, and apply them to Harvard's calorie calculator. The 125-pound runner is burning about 100 calories per mile. So running 5 miles at a 10-minute-per-mile pace would burn about 500 calories.

If you're an active woman, you should probably eat about 2,400 calories a day until age 30, according to the U.S. Dietary Guidelines. Active women aged 31 to 60 should eat 2,200 calories a day. Active men should eat about 3,000 calories a day until age 35, and about 2,800 calories a day from 36 to 55.

Read More: Ultramarathon Training Tips to Help You Finish Your First Race in One Piece

Once you've figured out how many calories you're burning, you can calculate how many extra calories you need to eat to fuel your run. You also need to assess your goals. If your goal is to run a fast race, you should eat differently than if your goal is to lose weight.

Runners need to consider these factors in choosing what they eat. Timing your meals to match the demands you're placing on your body can make all the difference in your training and racing, says the Mayo Clinic.

You need to make sure the calories you're eating provide the right mix of carbs, protein and fats. When you're training one to three hours per day, you should take in 2.7 to 4.5 grams of carbs per pound of your weight each day, says the Mayo Clinic. Carbs are the primary fuel source needed for endurance exercise, according to Andrea N. Giancoli, writing in the March 2016 issue of Today's Dietitian.

The American Council on Exercise (ACE) says as distance and running time increase, so do calorie and carbohydrate needs. The extra carbs help the muscles store glycogen, the body's primary energy source used while you're exercising. If you're regularly doing extended runs or training for a marathon, the ACE recommends a diet of 55 to 65 percent carbohydrates to store the optimal amount of glycogen. Runners should aim to get these carbs from whole grains and fruits, not simple sugars and highly processed foods.

Read More: The Best Recovery Drink After Running

Most runners are getting enough protein in their diet, and need only eat the recommended daily amounts of 0.6 to 0.8 grams of protein per pound of body weight. The Mayo Clinic recommends lean beef and pork, chicken, turkey, beans, nuts, eggs and low-fat dairy products.

There are no specific fat recommendations for runners, but the Mayo Clinic suggests healthy fats, including nuts, seeds, nut butters, avocado and olive or canola oil. The important thing about eating while training is to eat healthy foods.

Before a race or long training run, the Mayo Clinic suggests eating a low-fat meal, such as a turkey sandwich with baked chips and fruit, three to four hours before a race. If there isn't time for a meal, eat a snack an hour or two before. Cereal, yogurt, a bagel with peanut butter or cheese and crackers are good choices.

After the race or training run, recover with carbohydrates and protein. The carbs will replenish your muscle glycogen lost during the race, while protein will help with muscle repair.