Sports Nutrition for Endurance Athletes
If you fade late in a workout or competition, lack of fuel is a more likely culprit than lack of heart.
Good nutrition for endurance student-athletes starts with consuming enough carbohydrates (and enough food overall) to match your training. Get that right, and you’ll have steadier energy while you train and recover faster afterward.
This guide answers two practical questions for endurance athletes: What causes “the wall”? And are you eating enough? Let’s dive in.
Key Takeaways
Endurance student-athletes tend to under-fuel rather than overeat. And a lack of fuel can be the reason you fade late in races or training.
Research suggests aiming for roughly 6 to 10 grams of carbohydrate per kilogram of body weight per day (2.7 to 4.5 grams of carbs per pound of body weight), with the higher end on especially demanding training days.
For efforts past an hour, take in carbs early and steadily, about 30 to 60 grams per hour, and more for longer events if your stomach can handle it.
Practice fueling in training. Roughly two weeks of gut training can cut unabsorbed carbs by about half, which could help reduce stomach trouble on race day.
What Causes “the Wall,” and Can Nutrition Prevent It?
When you hit “the wall,” your muscles are running low on glycogen, the carbs your body stores for energy. Your blood sugar can drop, too. You might hear this called “bonking.” Your pace slows, your legs feel heavy, and everything else feels harder.
Sports nutrition for endurance athletes comes down to starting your workout or race well-fueled and consuming carbohydrates during longer efforts. Pacing yourself early matters, too.
A 2025 review of endurance carbohydrate research found that taking in carbohydrates during prolonged exercise can help keep blood sugar steady while muscle glycogen runs down, helping delay fatigue. Those carbs could come from a sports drink, chews, or fruit, depending on what you tolerate.
Nutrition isn’t magic, though. If you burn through your fuel by pacing too aggressively, you can still bonk.
For a broader look at fueling, check out our sports nutrition for athletes guide.
Are You Eating Enough for Your Training Volume?
Big training weeks need big fuel. A 2026 review on energy availability found that as training demands increase, athletes may not eat enough to match the energy they’re using. That can mean more fatigue, a harder time handling training, and less power.
A well-structured nutrition plan adjusts to the amount and intensity of the work you do. So, how do you know if yours is giving you enough fuel? If your progress stalls or you’re tired all the time, you may need to eat more. Poor sleep and mood swings can be clues, too. These signs can have other causes, like low iron, so talk with a doctor or sports dietitian to confirm.
On hard or high-volume days, eat more total food (especially carbs) and spread it across meals and snacks instead of trying to catch up at dinner.
If you need a place to start, a 2025 study on youth athlete nutrition provides the following targets for carbs, protein, and fat:
About 6 to 10 grams of carbohydrates per kilogram of body weight per day, or 2.7 to 4.5 grams of carbs per pound of body weight.
Roughly 1.4 to 2 grams of protein per kg of body weight daily, or about 0.6 to 0.9 grams of protein per pound of body weight.
Fat should typically account for about 20% to 35% of your total calories.
Here’s what those carb and protein ranges look like at different body weights:
Body weight | Kilograms | Approx. daily carb range | Approx. daily protein range |
100 lb | 45.4 | ~272.4–454 g | 63.6–90.8 g |
130 lb | 59 | ~354–590 g | 82.6–118 g |
160 lb | 72.6 | ~435.6–726 g | 101.6–145.2 g |
190 lb | 86.2 | ~517.2–862 g | 120.7–172.4 g |
No single meal or supplement has to hit these numbers. Carbs and protein add up across the day from rice, fruit, potatoes, beans, yogurt, snacks, and drinks.
Think of the table as a starting point, not a daily quota. A sports dietitian can help set individual targets, especially during big training blocks. To plan your day around training, see our guide to building a fueling timeline.
Carb-Loading Before Race Day Without the Bloat
The best nutrition for endurance student-athletes includes a carb-loading plan that starts before race day. One giant pasta dinner before generally won’t do the job.
For a long race, the 2025 endurance nutrition research we cited earlier supports increasing carbohydrate intake over the 36 to 48 hours beforehand to build glycogen (fuel) stores. A nutrition coach can help determine the right amount for you.
When prepping for a big race, choose familiar, easy-to-digest foods such as:
Rice
Potatoes
Pasta
Bread
Oatmeal
Bananas
Applesauce
Here’s what a sample menu might look like a day or two before your race:
Oatmeal with banana and honey for breakfast
Rice with grilled chicken and cooked vegetables for lunch
Pasta with lean protein and a simple sauce for dinner
As the race approaches, ease up on high-fiber and fatty foods that can upset your stomach.
Plan your race-day nutrition ahead of time and practice it in training. Our pre-competition fueling workshop can help you build that routine. On race morning, stick with a familiar, carb-rich meal or snack rather than trying something new or eating a huge breakfast.
Note: You might feel a little heavier while you carb-load. As your body stores more carbohydrate and glycogen, it also retains water, which can temporarily increase your weight.
Fueling During Long Efforts: How Much and How Often
For efforts under an hour, water is usually enough. Just make sure you drink regularly, when you start to feel thirsty, rather than waiting until you feel dehydrated.
Past the one-hour mark, your body does better with a steady supply of carbs, especially as the effort gets longer or harder. Start fueling early rather than waiting until you feel empty or tired.
The 2025 endurance nutrition review suggests eating roughly 30 to 60 grams of carbohydrate per hour for moderate-length events and up to about 60 to 90 grams per hour for longer ones. That research focuses on elite adult athletes, so treat these as starting points and check with a sports dietitian before aiming for the higher range.
Nutrition for ultra-endurance athletes gets even more individualized as events stretch on, so a nutrition coach or sports dietitian can help you find the right amount that your event and your stomach can handle.
If you’re anticipating a race that goes beyond an hour, you can get carbs from sources such as:
Sports drinks (~25g of carbs per 12 oz)
Energy chews (~25g – 35g of carbs per pack)
Energy gels (~20g – 25g of carbs per chew)
Bananas (~20g – 35g of carbs per banana)
Dates (~36g of carbs per two dates)
At higher hourly intakes, products containing both glucose and fructose may help the body absorb more carbohydrates. Check the label to see what’s inside.
Try different combinations in training and notice how your stomach responds. Practice your fueling and hydration strategies there, too, so nothing is new on race day.
Train Your Gut to Handle Fuel on the Move
Stomach trouble during a race doesn’t always mean your gut can’t handle fuel. Like your muscles, your digestive system can adapt with practice. A 2023 review of gut-training studies found that about two weeks of practicing carbohydrate intake during exercise cut the carbs the gut failed to absorb by roughly half. It also concluded that this kind of practice may reduce stomach discomfort.
Try this progression over a few weeks:
Start small: Take a few sips of a sports drink or half a banana during an easy workout.
Build gradually: If your stomach feels good, add more fuel during your next few sessions.
Make it race-specific: Practice your planned foods, amounts, and timing during workouts that match the length and effort of your event.
Good nutrition for endurance athletes comes down to familiarity, so if stomach trouble keeps showing up even with practice, check with a doctor or sports dietitian.
Recovery Nutrition: Refuel Fast After Long Sessions
Recovery nutrition for endurance student-athletes matters most when you have another workout or race soon. If you only have a few hours to recover, start eating soon after you finish an event.
Research suggests that during the first few hours after exercise, eating about 1 to 1.2 grams of carbohydrates per kilogram of body weight per hour can help restore glycogen quickly. That translates to about 0.45 to 0.54 grams of carbohydrates per pound of body weight, which is around 68g to 81g of carbs for a 150-pound athlete.
For best results, pair a carbohydrate-rich food with some protein. Easy options include:
Chocolate milk
Yogurt and fruit
A smoothie
Rice and chicken
If you sweat a lot, drink fluids and opt for a saltier meal or snack right after your race.
Plan your recovery fueling ahead of time ahead of time so you have something ready at the finish line.
Fueling and Staying at a Healthy Competitive Weight
Your body needs enough energy to train, recover, and grow. Eating less to change your weight takes energy away from all of that, and for a growing athlete, it isn’t a safe way to chase better performance.
The 2026 energy availability review we mentioned earlier warns that when you regularly eat too little for the work you do, your body can slip into low energy availability. Over time, that can:
Weaken your bones
Increase your risk of stress fractures
Disrupt hormones and menstrual cycles
Slow recovery and make hard training harder to handle
If body composition is a concern for your sport, don’t restrict food or start a weight-loss diet on your own. Talk with a doctor or sports dietitian who understands young athletes. Any change to your weight should be guided by one of them and shouldn’t mean eating less than your body needs.
You can also work with a nutrition coach to build a safe, individualized plan that supports both performance and long-term health.
How IMG Academy Helps Student-Athletes Fuel for Endurance
Putting endurance into practice takes more than knowing what to eat. IMG Academy+ Essentials brings nutrition into the same routine as training and mental performance, with on-demand, expert-built lessons on topics like:
Fueling timelines
Hydration
Pre-competition fueling
Recovery
Progress tracking in the app helps you turn what you learn into consistent habits.
For more personal support, IMG Academy+ Personal Coach connects you with a credentialed performance dietitian. Together, you’ll build a fueling and recovery plan around your training and competition schedule and your goals.
Conclusion: Fueling Up for the Long Run
Good nutrition for endurance student-athletes pays off most when you practice it every week. Start with eating enough for your training and health. Then fine-tune how you fuel before, during, and after long efforts. If you’re ever unsure whether you’re eating enough, ask a doctor or sports dietitian.
Ready to put it into practice?
Explore IMG Academy+ Essentials for on-demand nutrition, training, and performance content.
Connect with IMG Academy+ Personal Coach for one-to-one guidance from a credentialed performance dietitian.
Frequently Asked Questions
How do I carb-load without feeling heavy or bloated on race day?
Increase your carbohydrate intake over the day or two before a long race instead of eating one huge meal the night before. Choose familiar, easy-to-digest foods, reduce fiber and heavy fats as the race approaches, and keep race-morning food small and practiced.
What’s the real strategy for fueling during events over two hours?
Eat carbohydrates steadily throughout the event rather than waiting until you feel tired or empty. Research suggests consuming about 30 to 60 grams of carbs per hour for moderate-length events and up to 60 to 90 grams of carbs per hour for longer efforts.
How do I train my gut to handle food while moving?
Practice consuming carbs during workouts and gradually increase the amount over several weeks. A 2023 review of gut-training studies found that about two weeks of this practice roughly halved the carbs the gut failed to absorb.
Am I eating enough to support high training volume or running on empty?
You may be under-fueling if you consistently experience fatigue, poor recovery, declining performance, frequent injuries or illness, or disrupted sleep. If you are concerned, talk with a sports dietitian or physician who can help assess whether you are meeting your training and growth needs.
How do I balance endurance fueling with staying at a competitive weight?
Fueling adequately should come before trying to change your weight, because chronic under-eating can harm bones, hormones, menstrual cycles, recovery, and performance. Young athletes should seek professional guidance before making changes to their body composition or weight.
What causes the wall, and can nutrition really prevent it?
The “wall” is commonly linked to depleted muscle glycogen during prolonged exercise, and regular carbohydrate intake can help delay it. Starting well-fueled, eating carbohydrates during long efforts, and pacing appropriately can all help maintain energy.
