Good race nutrition starts in the final week, not on the start line. For most races, eat normal, balanced meals built from familiar foods during race week, increase carbohydrates in the last two to three days before a half or full marathon, have a tested, carb-based breakfast two to three hours before the start, and take in carbohydrate during races longer than about 75 to 90 minutes. Afterward, refuel with carbohydrates, protein and fluids. The golden rule is nothing new on race day: practice every part of your fueling plan in training first.
Health note: This is general information, not medical or dietary advice. Individual needs vary with body size, event, climate and health. Consult a doctor or registered dietitian for personal guidance, especially if you have diabetes, food allergies or intolerances, digestive conditions or a history of disordered eating.
Race nutrition timeline
| When | What to do |
|---|---|
| Race week | Normal, balanced meals with familiar foods; nothing new |
| 2 to 3 days out (half or full marathon) | Increase carbohydrate intake; reduce fiber and fat if you are sensitive |
| Night before | Familiar, carb-rich dinner of normal size |
| 2 to 3 hours before | Tested breakfast such as toast, oats, bagel or banana |
| During races over 75 to 90 minutes | Gels, chews or sports drink at regular intervals |
| After | Carbohydrates and protein plus fluids and electrolytes |
Race week: keep it familiar
During race week, training volume drops as you taper, and it can be tempting to experiment with new diets, supplements or restaurants. Resist that urge. Stick with meals you know agree with you, eat regularly and stay hydrated. Because you are running less, you may not need to eat much more overall, but make sure carbohydrate-rich foods such as rice, pasta, potatoes, bread, oats and fruit remain a steady part of your meals. For races of 5K or 10K, normal eating throughout the week is usually all that is needed.
Carb-loading for longer races
Carb-loading means increasing carbohydrate intake for the day or days before a long race to top up glycogen, the stored carbohydrate your muscles use for fuel. It is most useful for events lasting longer than about 90 minutes, such as the half marathon for many runners and the marathon for almost everyone. Sports nutrition guidelines often suggest around 10 to 12 grams of carbohydrate per kilogram of body weight per day for 36 to 48 hours before a marathon, though many recreational runners use a more moderate increase that feels comfortable.
Carb-loading does not mean eating huge amounts of food. It means shifting the balance of your meals toward carbohydrate while reducing some fat and fiber so the total volume stays manageable. Practical options include white rice, pasta, bagels, pancakes, potatoes without skins, juice, sports drinks and low fiber cereals. Some runners gain a small amount of weight during carb-loading because glycogen is stored with water; this is expected and not a sign of eating too much.
The night before
Your dinner the night before should be familiar, carbohydrate-rich and a normal size. A giant pasta dinner can leave you uncomfortable in the morning. Avoid very spicy, greasy or high fiber foods if they upset your stomach, and limit alcohol, which can affect sleep and hydration. Eating a little earlier in the evening gives more time for digestion.
Race morning breakfast
Eat your pre-race breakfast about two to three hours before the start. Choose foods that are high in carbohydrate and low in fat, fiber and protein, such as toast or a bagel with jam or honey, oatmeal, a banana, rice cakes or a sports drink. Guidelines often mention around 1 to 4 grams of carbohydrate per kilogram of body weight in the hours before a long event, with smaller amounts closer to the start. If your stomach is sensitive, a liquid meal such as a smoothie or sports drink may feel easier. Many runners also have a small snack, such as a gel or a few chews, 10 to 15 minutes before the start of a longer race.
Fueling during the race
For races under about an hour, most runners do not need to eat during the race, though sipping water or sports drink can help in warm weather. For longer races, taking in carbohydrate helps maintain energy and delay fatigue. Common guidance is around 30 to 60 grams of carbohydrate per hour, with some runners in long events training their gut to handle up to about 90 grams per hour using products that combine glucose and fructose. In practice, many runners take a gel or a portion of chews every 30 to 45 minutes, washed down with water. Start fueling early in the race rather than waiting until you feel tired, since it takes time for carbohydrate to be absorbed.
Hydration and electrolytes
Drinking to thirst is a sensible approach for most runners in most conditions. Drinking far more than you sweat can lead to a dangerous drop in blood sodium called hyponatremia, especially in slower runners in long races, so avoid forcing down large amounts of water. In hot or humid conditions, or if you sweat heavily, sports drinks or electrolyte tablets can help replace sodium lost in sweat. Check the race information for aid station locations and what drinks are provided, and practice with the same product in training if possible.
After the race
After you finish, start with fluids and some easy carbohydrates, such as a banana, sports drink or bagel. Within a few hours, eat a proper meal with carbohydrates and protein to help replenish glycogen and support muscle repair. Examples include a sandwich with lean protein, rice with chicken or tofu, or yogurt with fruit and granola. Continue drinking to thirst, and include salty foods if you sweated heavily.
How to build your race nutrition plan
- Choose your products early, ideally those offered on the course.
- Test your breakfast before long training runs at race start time.
- Practice fueling during long runs at the same intervals you plan to use.
- Train your gut by gradually increasing carbohydrate intake during long sessions.
- Plan carb-loading for two to three days before a half or full marathon.
- Write down your plan with times and amounts, and pack everything the night before.
Common mistakes to avoid
- Trying new foods or gels on race day.
- Overeating the night before and waking up uncomfortable.
- Eating high fiber or fatty foods right before a race.
- Waiting too long to fuel during long races.
- Overdrinking water, which can cause hyponatremia.
- Skipping recovery nutrition after the finish.
Frequently asked questions
Do I need to carb-load for a 5K?
No. Normal balanced eating is enough for most races under about 90 minutes.
What should I eat before a race?
A familiar, carb-based breakfast two to three hours before, low in fat and fiber.
How often should I take gels in a marathon?
Many runners take one every 30 to 45 minutes, starting early, based on what they practiced.
