When this is exhausted, the body then taps into stored glucose, called glycogen, in your liver and muscles. The rate at which glycogen is depleted depends on the intensity and duration of exercise and how much glycogen is stored..

When the glycogen is depleted, fat is then burned as a backup energy source. For fat to be used for energy, it must be broken down into fatty acids and other components, which requires time and makes it a less-efficient fuel source.

Regular running also will train your body to be better at converting fat to fuel. Long-distance runners should aim to get most of their calories from carbohydrates — the body's preferred fuel source. Choose complex carbohydrates, such as pasta, oatmeal and potatoes, for sustained energy.

Before a long run, focus on simple carbohydrates that can be used immediately. Sources for these include fruit, regular sports drinks and energy gels. During a long run or race — generally more than 90 minutes — aim to consume 30 to 60 grams of carbohydrates every hour.

This goal can be met with beverages or food. Two cups of a regular sports drink contain about 30 grams of carbohydrates.

Because fats aren't quickly converted to energy, avoiding a high-fat meal before a run is best. Instead, make fats part of your meals throughout the day. Focus on healthy fats from seeds, nuts, fatty fish, hummus and avocados. While protein isn't necessarily a fuel source during a run, it's essential for muscle repair after a run.

Eating adequate protein will allow you to recover more quickly. Choose good sources of protein throughout the day at meals and within 30 minutes after a workout for optimal recovery.

Good protein sources include meat, chicken, fish, eggs, dairy products, tofu and beans. Specific needs for calories, carbohydrates, protein and fat differ from person to person and depend on age, gender, activity level and medical conditions.

The months spent training for your race allow you time to optimize your diet. Most runners can figure out what works best for them with trial and error. However, seeking guidance from a registered dietitian can help simplify the process of fueling your run. Try this orange juice smoothie for a pre- or post-run recovery snack.

Some examples include:. If you decide to start on empty , you should have enough energy stores to last for a shorter run. But if you have time for a light snack, a piece of toast with jam or half of an energy bar can be a good choice.

Focus on carbohydrates and easy-to-digest foods. If you run in the evening and it's been a few hours since lunch but you haven't had dinner yet , try eating a healthy calorie snack about 60 to 90 minutes before a run, unless you are used to something else.

If it is within 60 minutes of a run, choose an easy carbohydrate that doesn't exceed 30 grams of carbohydrates, like a banana. If you've had issues with gastrointestinal distress also known as runner's trots during or after your runs, the foods you're eating the 24 hours before your runs may be the culprit.

Try limiting or eliminating some of these foods before running to see if it makes a difference:. Safer pre-run foods to avoid runner's diarrhea include:. While people often plan what they eat before and after a run, there may be times that you need to eat mid-run as well.

This is particularly true if you are running long distances. Most of the energy to fuel your efforts comes from glycogen stored in your muscles. However, once these stores are depleted, your body will begin drawing on sugar stored in the blood and liver.

If you are running for 90 minutes or longer, you will need to consume carbohydrates to replace your lost glucose. Sports drinks provide hydration, carbohydrates, sodium, and potassium. Sports gels and chews can also be a good choice. They usually provide carbohydrates in the form of fast-digesting sugars.

Some good mid-run options include:. Some runners even opt for high-sugar snacks like gummy bears or other small candies. The key is to choose something light that has high glycemic index carbs. Avoid foods that are difficult to chew and swallow during your run. You should also avoid spicy foods, dairy products, and high-fiber foods since they can cause tummy troubles.

What you eat after a run often depends upon your goals. For example, you might opt for lower-calorie choices if you are trying to lose weight or focus on higher-protein choices if you are trying to build muscle.

In any case, you will need to replace lost fluids, restore glycogen levels, and rebuild muscle fibers. Good post-run options include snacks or light meals containing fluids, carbohydrates, and protein, such as a bagel with nut butter , a protein shake, or Greek yogurt with a piece of fruit.

According to one study published in the Journal of the International Society of Sports Nutrition , chocolate milk might be a better choice than sports drinks for exercise recovery.

Skip high-fat, fried, or greasy foods high in calories but low in nutritional value. You might feel starved, but loading up on high-calorie fast food can undo all the benefits of your run. Sugary sodas are also a poor choice. We've tried, tested, and reviewed the best protein shakes.

If you're in the market for a protein shake explore which option may be best for you. The amount you need to drink before, during, and after a run depends on factors such as how long you will be running and your sweat rate.

While guidelines for specific amounts of fluid used to be provided for runners, newer guidelines recommend a more personalized approach. Studies have found that a personalized hydration plan based on sweat loss is best for optimal performance.

The latest position stand from the American College of Sports Medicine ACSM also recommends an individualized approach to workout hydration. According to the ACSM, when hydrating before exercise, you should slowly drink beverages at least four hours before exercise.

A volume of about 5 to 7 milliliters per kilogram of body weight is offered as a general starting point. But if you do not produce urine, or the urine is dark or highly concentrated, you should slowly drink more for example, another 3 to 5 mL per kilogram of body weight about two hours before the event.

If calculating your exact hydration seems too complex, it may be helpful for some runners to use age-old guidelines often provided by running coaches. If you plan to run for around 45 minutes, you will want to pre-hydrate by drinking around 17 to 20 ounces of fluid about two hours before your run, and 10 to 12 ounces of water or a sports drink 0 to 10 minutes before exercise.

You will want to maintain hydration levels during exercise. The ACSM recommends fluid consumption early and at regular intervals during training. But it does not provide a specific guideline for volume, noting that variations in clothing, duration, weather, and other factors come into play.

The organization recommends using your sweat rate to determine your personalized needs. You can use 0. The ACSM advises that beverages containing electrolytes and carbohydrates can help sustain fluid-electrolyte balance and exercise performance.

Replacing lost fluids is also vital following your run. But in many cases, you can just eat and drink normally to return to a balanced state. If you are dehydrated, drink about 1. If you become very dehydrated, you may need intravenous fluids. Preparing for a race or marathon requires good nutrition in addition to your physical training.

In the weeks before an event, you should also spend some time familiarizing yourself with what will be available during the race e. Well in advance of your event, you should start paying attention to how your nutrition influences your training.

What foods and meal timing works best for you? Following different nutritional strategies during your training might be beneficial. For example, if you are running shorter runs, there is probably no real need to increase your overall calorie or carbohydrate intake.

Distance runs that pass the minute mark should also include the addition of supplemental nutrition. This includes ensuring that you are replacing lost fluids to stay hydrated. Before a race or marathon, runners sometimes engage in what is known as carb-loading or consuming more significant amounts of carbohydrates in the two or three days before the event.

The goal is to maximize the stores of glycogen in the muscles during a race, which can improve endurance and prevent fatigue. This practice used to be more common, but many runners today prefer to increase their daily carb intake in the days before an event. Carb loading should be done with caution, and you should always make sure that you are also eating an adequate amount of protein.

Overeating or suddenly changing your eating habits right before a race can result in discomfort, decreased performance, and even gastrointestinal issues. Unlike race day weather or course conditions, your nutrition is one area you have complete control over.

With proper planning of your pre-race meal, you'll feel more confident and prepared to know that you already have a nutrition plan worked out. Runners have unique nutrition needs and considerations.

It's vital to properly fuel your training and recovery so you can feel and perform your best. As well, having a solid plan for race day can give you a competitive edge, providing you with enough energy for performance while avoiding potential gastrointestinal issue.

What works for you may be different than what works for other runners, so it is also wise to track your food intake and how it makes you feel during training. Then you can get a solid understanding of how your nutrition is affecting you and make adjustments. You should wait one and a half to two hours after a small meal before you run.

Alternatively, have a small snack 30 minutes to one hour before running. Experiment to see what works best for you. Elite marathoners consume different diets based on their body weight and training schedule.

Marathon runners adjust their diet depending on when they will be competing. However, endurance runners tend to consume more carbohydrates than the regular population approximately 8 to 10 grams of carbohydrate per kilogram of body weight each day.

They need more calories than those who do not run long distances due to the vast amount of calories the activity burns. Runners who want to fuel performance without shedding pounds will benefit from a diet that is higher in calories than what it would usually take to maintain weight.

If you have been running and are experiencing unwanted weight loss, increase your calories with larger portion sizes of nutrient-dense foods, or by adding a nutritious daily meal or snack. Start small and add more until you reach and maintain your desired weight.

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