Updated: 12/2/25
If you’ve ever wondered how to carb-load before a big race or event, it’s not just about eating pasta the night before. Carb-loading is a precise performance strategy designed to maximize glycogen, the body’s stored form of carbohydrate, to help you perform longer and stronger. When done correctly, it can improve endurance by up to 3%, a meaningful difference between a good performance and a personal best.
Carb-loading involves increasing carbohydrate intake in the 2 to 3 days leading up to endurance events lasting longer than 90 minutes. The goal is simple: fully stock your body’s glycogen stores so your muscles have the energy they need to perform at their best when fatigue sets in.
At Evogen, we know success is built on preparation. Whether you’re chasing a marathon PR or hitting a new personal record in the gym, fueling smart makes all the difference.
What Carbohydrate Loading Is
Carbohydrate loading is the process of boosting carbohydrate intake while reducing training intensity before competition. The result? Muscles soak up glycogen like sponges, storing extra energy to power you through long, intense efforts.
During a typical training phase, carbohydrates make up about 45 to 65% of daily calories. In a carb-loading phase, that jumps to 70 to 80%. For a 150-pound athlete eating 2,500 calories per day, that’s about 450 to 500 grams of carbs.
These extra carbs saturate your glycogen stores, giving you a performance advantage when intensity spikes. Every gram of glycogen binds to about three grams of water, so if your scale goes up a few pounds, that’s actually a sign you’re loaded, hydrated, and ready to go.
Understanding Glycogen And Energy Storage
To truly understand carb-loading, it helps to know what glycogen actually does. Glycogen is the body’s preferred form of stored energy. When you eat carbohydrates, your body breaks them down into glucose, which fuels your muscles and brain. Any glucose not immediately needed is stored in your muscles and liver as glycogen. During long workouts or competition, your body taps into those stores for energy.
As those glycogen stores run out, your performance dips sharply. That “hitting the wall” feeling in endurance events or that flat, tired look before a bodybuilding show both trace back to depleted glycogen. By completing a structured carb-loading phase, you’re topping off your energy reserves to delay fatigue and keep power output high.
At Evogen, we see this process as strategic preparation, not guesswork. Our GlycoJect was formulated to help athletes refill muscle glycogen faster and more efficiently, especially during multi-day events or intense training blocks.
Why Carb-Loading Works
Your body relies on glycogen as its primary energy source during endurance exercise at 65 to 85% of your max heart rate. Once those stores run low, your pace drops, fatigue rises, and performance declines. Carb-loading prevents that energy crash by ensuring your muscles are fully fueled.
Research suggests that athletes who start with full glycogen stores can extend time to exhaustion by up to 20%. Studies and systematic reviews confirm that proper carbohydrate loading improves exercise performance in events lasting more than 90 minutes.
When done right, carb-loading doesn’t just help you last longer, it helps you finish stronger.
Timing Your Carb Loading Phase
Timing matters as much as quantity. For most athletes, the carb-loading phase should begin 48 to 72 hours before competition. This is when you taper training intensity to help glycogen accumulate without being burned off immediately. If you train hard while loading, you risk using the carbs for recovery rather than storage.
The best approach is to schedule your final intense workout three to four days before race day, then reduce duration and intensity while increasing carb intake. That combination primes your muscles to hold more glycogen. During this window, your metabolism becomes highly receptive to glucose uptake, especially when paired with sodium and hydration.
We always encourage athletes to plan this window around their schedule. Proper timing is the difference between just eating more carbs and executing a real carb-loading strategy that delivers results.
How Much To Eat During The Carb-Loading Phase
The sports nutrition position stand recommends 8 to 12 grams of carbohydrates per kilogram of body weight during the loading phase. Start on the lower end if you’re new to the process, and build up based on comfort.
- 50kg athlete: 400 to 600g carbs per day
- 70kg athlete: 560 to 840g carbs per day
- 90kg athlete: 720 to 1,080g carbs per day
For most endurance athletes, that’s about 70 to 80% of total calories. Spread your intake across five to six smaller meals and snacks each day to keep digestion smooth and energy steady.
To make meeting your carb targets easier, use convenient sources like our GlycoJect, a high-performance super carb formula that delivers fast-digesting carbs without bloat.
A Practical Meal Plan for the Carb-Loading Phase
Think of the carb-loading phase as a focused, short-term nutrition adjustment, not a license to overeat. The goal is to increase carbs without overwhelming your digestive system.
Choose Low-Fiber, Easily Digestible Carbs
During the loading phase, skip high-fiber foods that slow digestion or cause discomfort. Stick to options like:
- White rice, pasta, or plain bagels
- White potatoes or rice cakes
- Simple cereals and pretzels
- Fruit juices or low-fiber fruits like bananas
These foods help store glycogen efficiently without adding unnecessary fiber or fat.
Use Liquid Carbs To Boost Intake
Sports drinks and carb powders can help when whole foods feel too heavy. Drinks like our GlycoJect or other fast-digesting carb sources make it easier to hit your numbers without feeling stuffed.
Include Protein And Healthy Fats In Moderation
Keep protein steady at about 1.2 to 1.4g per kilogram of body weight and limit fat to 15 to 20% of total calories. Choose lean proteins and small portions of healthy fats like olive oil or avocado to support recovery without slowing digestion.
Sample Carb-Loading Day Plan
Here’s an example of what a structured carb-loading day could look like for an endurance athlete or bodybuilder:
- Breakfast: White rice with honey and banana, or pancakes made with low-fat milk.
- Mid-morning snack: Plain bagel with jam and a small serving of our GlycoJect.
- Lunch: White pasta with a lean protein like chicken breast and a small drizzle of olive oil.
- Afternoon snack: Rice cakes with honey or a small fruit smoothie.
- Dinner: Baked white potatoes with grilled fish and a light sauce.
- Evening snack: A glass of juice or a sports drink before bed to top off glycogen stores.
The goal is to eat familiar foods evenly throughout the day while staying hydrated. This plan avoids high-fiber vegetables, heavy fats, and sauces that could interfere with absorption. For athletes in the carb-loading phase, simplicity is power. Fuel clean, rest well, and wake up ready.
Foods To Avoid During Performance Week
During your carb-loading phase, stay away from foods that slow digestion or cause GI issues:
- High-fat foods: creamy sauces, fried foods, chips, cheese-heavy meals.
- High-fiber foods: beans, cruciferous vegetables, whole grains, high-fiber bars.
- Unfamiliar foods: now’s not the time to experiment with new cuisines or supplements.
The goal isn’t variety; it’s control. Stick with foods you know digest well, and keep energy stable.
Hydration And Glycogen Storage
Carb-loading doesn’t work without proper hydration. Every gram of glycogen stored in your muscles binds to about three grams of water. Without enough fluid, you’ll limit how much glycogen your body can retain.
Drink about 0.5 to 1 ounce of water per pound of body weight daily during your loading phase. Include sodium to help your body retain fluids, as sports drinks can be useful here.
Well-hydrated muscles are more responsive, more powerful, and better prepared for high-intensity activity.
Hydration Strategy For The Carb-Loading Phase
Hydration deserves its own focus during carb-loading. Water alone isn’t always enough. To fully store glycogen, your muscles also need sodium, potassium, and other electrolytes. Without them, you risk poor fluid retention and cramping during your event.
Start by including 500 to 700 milligrams of sodium in each main meal while loading. Add small amounts of electrolytes to your fluids, especially in hot or humid conditions. Pairing carbohydrates with electrolytes not only supports hydration but also improves glucose transport into muscle cells.
We recommend sipping fluids gradually to avoid bloating. Think of hydration as part of fueling, not an afterthought. When glycogen and hydration peak together, you’ll notice steady energy and lasting control from start to finish.
Performance Products That Support PR-Level Results
At Evogen, we’ve spent years perfecting nutrition solutions that help athletes perform at their absolute best. During the carb-loading phase, pairing your nutrition with smart supplementation can make a measurable difference in how you feel and perform.
Athletes chasing a PR often combine our GlycoJect before or during long training sessions with our Evolog alongside high-carb meals. This nutrient partitioning support helps shuttle glucose directly into muscle tissue for stronger glycogen loading and faster recovery.
Electrolyte balance matters just as much as carbs. These products deliver sodium, potassium, and carbohydrates in a ratio designed to keep muscles firing without cramping. Keep fats low while loading, focus on hydration, and follow the plan you practiced during training.
Our CEO and founder, Hany, always says success is about precision, not luck. Carb-loading with the right combination of foods, supplements, and discipline turns preparation into performance.
Carb-Loading For Endurance Athletes
Endurance athletes benefit the most from carbohydrate loading since their events, like marathons, triathlons, and long rides, can completely deplete glycogen stores.
Start your loading 2 to 3 days before race day, aiming for 8 to 10 grams of carbs per kilogram of body weight daily. Reduce training volume by 40 to 60% to conserve glycogen while you load.
On race morning, eat a familiar high-carb breakfast 3 to 4 hours before the start line. Good options include oatmeal with banana, white bread with honey, or a bagel with low-fat peanut butter. Avoid high fiber foods, and sip a light carb drink leading up to your warm-up.
During the event, aim for 60 to 90 grams of carbs per hour through gels, drinks, or chews to maintain performance.
Smart Fueling With Trusted Carb Sources
When you’re learning how to carb-load effectively, choosing the right carbohydrate sources can make or break your results. Not all carb powders or gels digest the same, and poor product selection is one of the main reasons athletes experience bloating or GI issues before competition.
We always suggest loading gradually, around 4 to 7 grams of carbs per pound of body weight, for 2 to 3 days leading up to your race or event. This approach lets your digestive system adapt while maximizing glycogen storage. If you find large carb meals cause bloating, adding our Evozyme can improve digestion and nutrient absorption.
The key is practicing your fueling plan well before race day. Test these carb sources during training, not during competition. The more familiar your body is with your carb strategy, the smoother your performance will be when it counts.
Carb-Loading For Different Sports
Carb-loading benefits extend beyond running. Cyclists, swimmers, triathletes, and CrossFit athletes use it to sustain performance. For endurance athletes, it extends time to exhaustion. For team athletes, it helps maintain high-intensity bursts.
In bodybuilding, carbs fill out muscle tissue, drawing water into muscle cells to enhance fullness and muscle density. The best time to eat carbs for muscle growth often aligns with competition prep or recovery phases.
We’ve seen that across sports, the core principle stays the same: maximize glycogen, control hydration, and fine-tune timing for your discipline.
Best Carb Drinks And Electrolyte Blends For Gut Comfort
If you struggle with stomach discomfort while carb loading, the fix isn’t eating less; it’s choosing smarter carb drinks and blends. The most popular options that support hydration and glycogen replenishment without GI distress include Maurten 160 or 320, Tailwind Endurance Fuel, Skratch Hydration Sport, Gatorade Endurance, and Precision Hydration 1000 or 1500, alongside our GlycoJect.
These blends are designed to deliver steady glucose and electrolytes without overwhelming digestion. For athletes with sensitive stomachs, it’s best to increase carbohydrates gradually 2 to 3 days before the event rather than loading all at once.
Carb-Loading For Bodybuilding
Carb-loading isn’t just for runners. In bodybuilding, it fills muscles with glycogen to create that full, dense look before stepping on stage.
The best time to eat carbs for muscle growth is typically 2 to 3 days before competition, peaking 24 to 36 hours before showtime. Bodybuilders often load with easily digestible carbs like white rice, rice cakes, or sweet potatoes.
Our Evolog supports this process by enhancing nutrient partitioning, helping shuttle glucose into muscle cells where it belongs. Combined with our GlycoJect, athletes can achieve fuller, harder muscle definition without unwanted water retention.
To maintain that look, competitors eat small carb feedings every few hours and stop large meals about 2 to 3 hours before stage time.
How Female Athletes Can Carb-Load Effectively
Carb loading works for everyone, but female athletes often respond differently due to hormonal shifts throughout the menstrual cycle. Research suggests that higher estrogen levels, especially during the luteal phase, enhance the body’s capacity to store glycogen and promote fat oxidation. In contrast, the follicular phase, when estrogen levels are lower, favors carbohydrate oxidation and faster energy use.
That means women may need to slightly increase carbohydrate intake in the luteal phase to reach full glycogen saturation, while those in the follicular phase can maintain moderate levels for optimal results. Tracking your cycle helps fine-tune timing and intake for better performance.
We encourage all athletes to understand their physiology as deeply as they understand their training. Hany, our CEO and Founder, has long emphasized that awareness and precision matter just as much as effort. Knowing when your body best stores glycogen allows you to align training, nutrition, and recovery for maximum output.
Practice Carb Loading In Training
You wouldn’t test new shoes on race day, and you shouldn’t test carb-loading then either. Use training sessions to practise your plan and see how your body responds.
Test foods, portion sizes, and timing strategies during long workouts or simulation events. Keep notes on how you feel, what digests well, and where adjustments are needed.
Each trial helps fine-tune your approach so race week is smooth, comfortable, and predictable.
Common Carb-Loading Mistakes To Avoid
Carb-loading seems simple, but small mistakes can make a big difference. Waiting until the night before the event is too late; true glycogen saturation takes two full days.
Avoid overeating fatty or high-fiber foods, which slow digestion and can cause discomfort. Skip unfamiliar meals or new supplements during your loading phase.
Finally, don’t neglect hydration. Glycogen binds with water, so without enough fluid and electrolytes, your muscles cannot store it effectively.
Different Strategies For Carb-Loading
There’s no one-size-fits-all carb-loading approach. Athletes use proven methods to reach peak glycogen levels:
Traditional 3-Day Load: Increase carbs gradually over three days while tapering training.
One-Day Rapid Load: Experienced athletes load aggressively at 10 to 12g of carbs per kilogram of body weight in one day.
Modern Loading Without Depletion: No need for depletion phases. Research confirms you can achieve the same glycogen storage through gradual loading.
Choose the method that fits your experience and event.
Post Carb-Loading: Transitioning Back To Normal Eating
After your event, avoid swinging to extremes. Focus on rebalancing your nutrition. Glycogen stores will deplete during performance, so refuel with both carbohydrates and protein in a 3:1 ratio within the first hour.
This combination restores glycogen and supports muscle recovery. Pairing your carbs with our Evozyme can enhance absorption and ease digestion after intense efforts.
Over the next few days, scale carbohydrate intake back to normal. If prepping for another competition, begin a lighter load again. The goal is metabolic flexibility and consistent recovery.
The Science Behind Carb-Loading
A systematic review found consistent 2 to 3% improvements in endurance performance among trained athletes. The sports nutrition position stand supports carbohydrate loading as one of the most effective ways to boost performance for events over 90 minutes.
Experts like Burke LM confirm that muscle glycogen can increase up to 100% above normal levels with proper loading. The International Society of Sports Nutrition and NSCA both emphasize personalized fueling strategies and consistent practice.
Fuel Smarter, Perform Stronger
Mastering carb-loading is about understanding your body and preparing it for success. Increase carbs, stay hydrated, and fine-tune your plan before the big day.
We’ve seen how precision fueling transforms results. From endurance athletes to bodybuilders, those who prepare with discipline perform with confidence.
If you’re serious about performance, use smart carb loading with science-driven support from our lineup, like our GlycoJect for rapid glycogen delivery, Evolog for nutrient partitioning, and Evozyme for digestive efficiency. Together, these tools help you fuel with purpose and perform without limits.
