Preparation is key for runners of any caliber.

Properly fueling your run helps minimize fatigue and speed up recovery.

On the other hand, fueling up on the wrong foods or not at all before a run can cause stomach cramps or lead to the dreaded “wall” — a phenomenon where energy levels plummet.

Here are some guidelines on how to fuel your run with the right meals and snacks.

It’s important to fuel up three to four hours in advance, particularly if you’re a distance runner (1).

Distance running includes events such as the 10-kilometer (6.2 miles), the half marathon (21 km or 13.1 miles) and the marathon (42 km or 26.2 miles).

If you’re running less than 60–90 minutes, a pre-run meal becomes less important (1).

The pre-run meal serves two purposes. One is to keep you from feeling hungry before and during your run, and the other is to maintain optimal levels of blood sugar for your exercising muscles.

The meal should be high in carbs, moderate in protein and low in nutrients that slow digestion, mainly fat and fiber.

Make sure to drink 17–20 ounces (500–590 ml) of water with your pre-run meal to ensure you’re adequately hydrated (2).

Here are some examples of a pre-run meal:

  • Five scrambled egg whites and one whole egg with two pieces of white toast with jelly and a banana.
  • One cup (225 grams) of low-fat cottage cheese with one cup (150 grams) of blueberries and one slice of white toast with one tablespoon of honey.
  • One medium-sized white bagel with two slices of deli turkey and mustard (if desired) with 30 grapes.
  • One medium-sized baked potato with sour cream and 3 ounces (85 grams) of grilled chicken breast with a dinner roll.
  • One cup (200 grams) of cooked pasta with 1/2 cup (130 grams) of marinara sauce with 3 ounces (85 grams) of chicken breast and a slice of lightly buttered bread.

Foods to avoid:

  • High-fat foods: Heavy sauces and creams, fried foods or foods prepared with a lot of butter or oil.
  • High-fiber foods: Whole grains high in fiber, beans and cruciferous vegetables like broccoli and cauliflower.
Summary

Three to four hours before a race or training session, distance runners should consume a meal that’s easily digested and absorbed by the body. An ideal pre-run meal is high in carbs, moderate in protein and low in fat and fiber.

A pre-run snack consumed 30–60 minutes prior provides your body with quick fuel.

It’s only necessary to have a pre-run snack if you intend to run for longer than 60 minutes, but it’s also fine if you simply prefer to do so regardless of the length of your run.

It serves the same purpose as a pre-run meal by controlling hunger and ensuring optimal blood sugar levels.

A pre-run snack consists primarily of carbs and is much lower in calories than a pre-run meal.

Keep the snack small, as exercising with too much food in your stomach can lead to indigestion, nausea and vomiting (2).

Sample pre-run snacks include:

  • A piece of fruit, such as a banana or orange
  • Half of a sports energy bar
  • Half of an English muffin with honey or jelly
  • 15 crackers, such as saltines or pretzels
  • Half-cup of dry cereal

In addition to your pre-run snack, drink 5–10 ounces (150–295 ml) of water to keep you hydrated (2, 3).

Limit the same foods you would in a pre-run meal, which include foods high in fat and fiber.

You may also want to avoid dairy products, especially if you don’t know how you tolerate them. Dairy products are made from milk and contain the sugar lactose.

For some people, consuming too much lactose can cause stomach distress, such as bloating, gas or diarrhea (4, 5).

Foods high in lactose are those that contain milk, cheese, butter or cream. Yogurt is also a dairy product but tends to be tolerated better since it’s lower in lactose (6, 7, 8).

Summary

A pre-run snack consists primarily of easily digestible carbs like fruit or crackers. Depending on how you tolerate dairy products, it may be best to avoid them before a run.

Your glycogen stores can become depleted within one to two hours of running (9).

Glycogen is the stored form of glucose, or blood sugar, that your body relies on when it needs more energy.

That said, to refuel and delay fatigue, it’s recommended to eat 30–60 grams of carbs per hour spaced 15–20 minutes apart for runs lasting longer than 90 minutes (2).

An intra-run snack can include:

  • Sports drinks: These drinks contain electrolytes, which you lose in sweat, and a high percentage of carbs to restore energy.
  • Energy gels: These concentrated sources of carbs contain sugar and other ingredients like electrolytes or caffeine. They come in small, single-serve disposable packets.
  • Energy bars: These tend to be high in carbs and moderate in protein. Protein helps your muscles recover and rebuild.
  • Other snacks: Dried fruit, packets of honey, gummy bears and other candies work just as well as their more expensive counterparts at restoring energy.

Regardless of your intra-run snack of choice, make sure it’s something that you can take on your run or will be available to you during a race.

Depending on how much you sweat, you’ll also want to drink water throughout the race. Do this by drinking 17–34 ounces (500–1,000 ml) of water per hour (2).

But be careful not to over-hydrate. If you drink 8 ounces (240 ml) of a sports drink in an hour, don’t drink 17–34 ounces (500–1,000 ml) of water in addition to that amount.

Summary

For runs lasting longer than 90 minutes, make sure to refuel with carbohydrate drinks, gels, bars or other convenient options to delay fatigue.

When it comes to fueling your runs, make sure to experiment with what works best for you.

For instance, you may find that white rice instead of a baked potato for your pre-run meal sits better on your stomach.

Or you may notice that eating a banana for your pre-run snack doesn’t give you stomach cramps during your run whereas an apple did.

Training runs are the best time to experiment with different foods to see what works best for you (10).

Never do anything new on race day that you didn’t do in practice because you risk not knowing how your body will react to that change.

Summary

Training runs offer the perfect opportunity to experiment with different foods and see how your body reacts to them.

Any endurance activity requires special attention to pre- and intra-run nutrition.

Fuel up on high-carb, moderate-protein meals 3–4 hours before a long-distance training run or event.

In the 30–60 minutes leading up to a run, stick with a light, high-carb snack.

For runs lasting longer than 90 minutes, make sure to fuel up with sports drinks or other snacks during the race.

Keep fat and fiber intake low in the pre-run meal and snack to ensure adequate time for digestion and absorption.

It’s important to experiment with different foods and beverages during training runs to see what fueling strategy works best for you.