Carbohydrate Loading Strategies for Endurance Athletes: A 72-Hour Pre-Race Meal Plan at 10 g/kg Body Weight and Recovery Scheduling

For long-distance cycling events, Gran Fondos, endurance off-road races, long mountain bike climbs, and road races at half-marathon distance or longer at paces near the lower threshold of lactate threshold, carbohydrate loading is not just “eating a bit more rice.” It is a quantifiable method to push muscle and liver glycogen to elevated levels, in exchange for steadier late-race pacing, maintained climbing power output, greater fueling error tolerance, and preserved cognitive function in the decisive segments. The truly valuable question is not “should I eat carbs,” but rather “over how many days, at what gram amount, with how much training taper, and in what form should I consume them to fill glycogen stores without bloating, diarrhea, or insomnia.”

One thing must be made clear upfront: the strongest direct research evidence in sports nutrition supports consuming 10 to 12 g/kg/day of carbohydrates for 36 to 48 hours pre-race, rather than all studies directly testing a “fixed 72 hours at 10 g/kg daily.” The “72 hours at approximately 10 g/kg daily” approach adopted in this article extends existing high-carbohydrate loading principles into an execution version that is easier to implement, gentler on the gastrointestinal system, and more athlete-friendly for Taiwanese competitors. This is an evidence-based practical inference, not an inference dressed up as dogma.

1. What Carbohydrate Loading Actually Loads: Muscle Glycogen, Liver Glycogen, and Central Performance

The value of carbohydrates in endurance sports is not primarily about total calories, but about “whether glucose oxidation can be sustained in high-power zones.” When cycling enters long climbs, headwinds, attacks, or surge accelerations, or when running enters the sustained high pace of the latter half of a marathon, ATP regeneration must accelerate. While fat oxidation has large total stores, it cannot fully take over high-intensity output. If muscle glycogen drops too early, the common result is not an immediate blow-up, but a chain of events:

• Perceived exertion suddenly rises at the same wattage or pace.
• Cadence or stride rate begins to drop, and neuromuscular coordination deteriorates.
• The ability to insert high-intensity efforts declines, and reactions become sluggish on climbs or during pace changes.
• Cognitive focus declines, degrading fueling decisions and pacing judgment.
• The latter stages shift to fat-dominant energy production, forcing a downward revision of the output ceiling.

Muscle glycogen primarily affects the output capacity of the locally working muscle groups. If a cyclist’s glycogen stores in the quadriceps, glutes, and gastrocnemius are low, the first signs are reduced pedaling torque and compromised rhythm stability. Runners are more likely to experience longer ground contact time, shortened stride length, and insufficient hip extension strength in the latter stages. Liver glycogen’s role leans toward maintaining blood glucose stability, preventing central fatigue, attention lapses, and slowed reaction times during prolonged exercise. Therefore, carbohydrate loading is not just about fueling the legs—it is also about keeping the brain in a state capable of “precisely executing the race strategy.”

2. Who Actually Needs to Load: Not Every Event Justifies It

Carbohydrate loading is most worthwhile under the following conditions:

• Estimated exercise duration exceeds 90 minutes, with a significant proportion at moderate-to-high intensity.
• Events requiring prolonged sub-threshold output, such as mountain biking, hilly road cycling, triathlon bike legs, and road races at half-marathon distance or longer.
• Race-day fueling is constrained—for example, technical off-road courses with long gaps between aid stations, or heat reducing gastrointestinal tolerance.
• Recent training volume is high, and daily muscle glycogen is often only half-full, making pre-race taper the ideal window for supercompensation.

Conversely, if the event is only 45 to 60 minutes, or long but at very low intensity, the marginal benefit of loading is usually less valuable than focusing on the pre-race meal, in-race fueling, sleep, and hydration/electrolyte management. If short-distance athletes force carbohydrate intake to 10 g/kg/day, the most common outcomes are not speed gains, but water retention, gastrointestinal bloating, and psychological stress from weight gain.

3. What the Research Evidence Says: 36 to 48 Hours of High Carbohydrate Is the Core; 72 Hours Is a Practical Optimization

The mainstream recommendation in sports nutrition position stands for pre-race loading before prolonged endurance events is 10 to 12 g/kg/day for 36 to 48 hours. The goal of this range is clear: against the backdrop of pre-race tapering, bring muscle glycogen into a high-storage state, thereby improving prolonged exercise performance. Newer practical perspectives have also long moved away from the earlier extreme approach of “depletion first with low carbohydrate, then refilling with high carbohydrate,” because the low-carbohydrate depletion phase increases the risk of reduced training quality, elevated immune stress, and mood swings—and there is currently no sufficient evidence to prove that approach is superior to direct high-carbohydrate loading.

So why does this article still adopt a 72-hour plan? There are three reasons:

1. Higher gastrointestinal feasibility
   Compressing total carbohydrate intake into the final 36 hours often means consuming 650 to 960 grams of carbohydrates per day for athletes weighing 65 to 80 kg. If daily fiber intake is high, protein intake is high, or baseline appetite is small, the last two days become extremely uncomfortable, and bloating and appetite collapse often prevent reaching the target.

2. Training taper naturally reduces expenditure
   When total training volume is reduced starting 72 hours pre-race—especially lowering long-duration and high-volume sessions—glycogen depletion slows. Starting high-carbohydrate distribution earlier allows stores to be gradually filled without forcing it.

3. Research already shows high glycogen states can be achieved in a short time and maintained for a period
   Some studies show that with significantly reduced activity and a high-carbohydrate diet, muscle glycogen can rise substantially within 24 hours. Additionally, the supercompensated high-glycogen state does not disappear within hours; as long as training volume is controlled and sufficient carbohydrate intake continues, it can be maintained for several days. This makes the 72-hour plan physiologically reasonable.

Therefore, the most rigorous statement should be: if pursuing the most direct correspondence to the literature, use 10 to 12 g/kg/day for 36 to 48 hours; if pursuing higher completion rates and lower gastrointestinal risk, spread the target across 72 hours at approximately 10 g/kg per day.

4. Numerical Formulas and Total Intake Estimation: Calculate Correctly First, Then Discuss Menus

The most common failure is not a conceptual error, but a failure to calculate at all. “Eating more” and “meeting loading standards” are usually very different things.

Core Formulas

• Daily carbohydrate target = body weight (kg) × 10 g
• If using the upper literature version = body weight (kg) × 10 to 12 g
• Pre-race preparatory meal 1 to 4 hours before = body weight (kg) × 1 to 4 g
• If two high-quality sessions or prelim/final races are less than 8 hours apart, the first 4 hours of recovery = body weight (kg) × 1 to 1.2 g/h

Common Body Weight Reference Table

These numbers look large because high-carbohydrate loading is not a general healthy eating ratio—it is a short-term, targeted, tactical nutritional operation in service of competition. When you see that a 70 kg athlete needs 700 grams of carbohydrates per day, you understand why two bowls of rice and a banana are nowhere near enough.

Practical Portion Concepts for High-Carbohydrate Foods

The real execution focus is making meals, snacks, and liquid carbohydrates work together, rather than forcing solid starches alone.

5. The 72-Hour Loading Schedule: A Practical Version for a 70 kg Athlete

Below is a version designed for high completion rates, low fiber, and easy access to common Taiwanese ingredients. Assume the race starts at 6:00 AM on Sunday, with the last meaningful workout completed on Thursday, and the loading window running from Friday through early Sunday morning.

D-3: Start Tapering, Raise Carbohydrate Density First

The goal isn’t to binge-eat, but to ensure every meal from the first one has a clear carbohydrate base. A very short spin or rhythm session can be kept on this day, but avoid excessive total volume.

In practice, a 70 kg athlete doesn’t necessarily need to force down 850 g every day. If gastrointestinal pressure is high, D-3 can aim for 8.5 to 9.5 g/kg first; the key is to steadily raise total intake to build the foundation for D-2 and D-1.

D-2: The Main Loading Day, Prioritize Hitting the Target

D-2 is usually the most critical day. Training volume is lower, performance anxiety starts to creep in, and many people get the itch to ride or run a bit more—only to burn off the glycogen they just loaded. The principles for this day are:

• If activity is needed, do only short, low-intensity work and a few neural-activation sets.
• Keep fiber low; avoid large amounts of raw vegetables, beans, fried nuts, and lots of fruit with skin.
• Keep protein adequate but not excessive; don’t waste stomach capacity on big steaks.

The suggested menu can be simplified further:

• Breakfast: 3 bowls of congee, pork floss, 4 slices of white toast, honey, 2 bananas.
• Morning: rice crackers, juice, sports drink.
• Lunch: 3 to 4 bowls of white rice, chicken breast or fish, small amount of cooked carrots or pumpkin.
• Afternoon: bagels, jam, low-fat yogurt, rice milk.
• Dinner: pasta or a white rice main dish, clear soup, low-fat meat.
• Before bed: cereal, milk, sports drink or malt drink.

For a 70 kg target, aiming for 700 to 780 g of carbs on D-2 is reasonable. The most helpful trick here is to convert part of the carbohydrate intake into liquid form—such as juice, rice milk, sports drinks, congee, or low-fiber cereal—for faster gastric emptying.

D-1: Save the Glycogen for Tomorrow, Don’t Overeat Tonight and Ruin Your Sleep

Two common mistakes occur on the final day: the first is eating too little due to nerves; the second is overloading at dinner and dealing with acid reflux at midnight. The key for D-1 isn’t to eat more than the previous day, but to hit the target steadily, finish early, and minimize gastrointestinal residue.

Operating principles:

• Move dinner earlier, finishing 3 to 4 hours before bedtime.
• Put the bulk of carbohydrates between breakfast and the afternoon.
• Avoid overly spicy, greasy, dairy-heavy foods, excessive caffeine, and alcohol in the evening.
• If you have to get up very early and the pre-race breakfast will be hard to finish, make sure D-1 total intake is sufficient.

A workable example:

Whether D-1 needs to reach 10 g/kg depends on how well the previous two days went and personal appetite. If D-3 and D-2 were fairly complete, 8.5 to 10 g/kg on D-1 is usually sufficient.

6. Bridging the Pre-Race Breakfast, In-Race Fueling, and Loading

Many people mistakenly believe that a successful load means they can ignore fueling on race day. That’s a classic error. Loading only enlarges the fuel tank at the start; it doesn’t mean you stop burning fuel during the race.

The Pre-Race Meal 1 to 4 Hours Before

Research suggests 1 to 4 g/kg. In practice, it depends on the start time:

• For a 5:00 to 6:00 AM start, you can usually only eat 1 to 2 g/kg 2 to 3 hours before.
• For an 8:00 to 9:00 AM start, you can eat 2 to 3 g/kg 3 to 4 hours before.
• Athletes with very stable stomachs may go up to 4 g/kg for specific events, but that’s not the starting point most people need.

If a 70 kg runner needs 2 g/kg 3 hours before the race, that’s about 140 g of carbs, which could look like:

• 6 slices of white toast with jam.
• 2 bananas.
• 500 to 600 ml of rice milk or sports drink.

The key for this breakfast is low fiber, low fat, low irritation, and familiar. Don’t test new energy bars, ultra-high-fiber oatmeal bowls, or super-thick shakes on race day.

In-Race Fueling

If the event lasts more than 2 hours, even a perfect load still calls for mid-race fueling. Common guidelines are:

• For medium-to-long endurance events: 30 to 60 g of carbs per hour.
• If the event exceeds 2.5 hours and the gut has been trained, intake can be raised to around 90 g per hour.
• For mountain bike cross-country or technical courses, fueling frequency often matters more than a single large dose, because eating opportunities are fragmented.

The difference between cycling and running:

• On the bike, it’s easier to take in fluids and gels, so the total ceiling is usually higher.
• In running, because of the impact and jostling, chasing 90 g/h without prior gut training can easily backfire.

The conclusion is straightforward: Pre-race loading determines how big your starting fuel tank is; in-race fueling determines whether you can make that tank last long enough.

7. Recovery Scheduling: What to Do If You Still Have Workouts Before the Race, or Need to Refill Quickly Afterward

Carbohydrate loading and recovery nutrition are not two separate systems. Many cyclists still do short interval openers on Friday, and runners may keep a rhythm session two days before the race. Whenever recovery time between two key sessions or pre-race activities is short, you need to maximize refueling efficiency.

When Another High-Quality Output Is Needed Within 8 Hours

Use the “rapid refill” logic: 1 to 1.2 g/kg of carbs per hour for the first 4 hours. For example, a 60 kg athlete finishing a morning workout needs roughly 60 to 72 g of carbs per hour for the next 4 hours. This can be broken down as:

• Within 30 minutes after exercise: 500 ml recovery drink plus a banana or white toast.
• Hours 1 to 2: white rice, rice noodles, bagels, juice.
• Hours 3 to 4: keep topping up with low-fat starches and drinks.

If carbohydrate intake is insufficient or total calories are low, adding protein can help refueling efficiency, but only if the carbohydrate itself reaches the target. You can’t replace glycogen refilling with a “high-protein shake.”

Post-Race Recovery Should Also Consider the Next Day’s Quality

If you finish a long road ride today and have a long run or recovery ride tomorrow, the recovery dinner should still be carbohydrate-dominant. A common mistake is going straight for barbecue and fried food after the race—high in protein, but not enough carbs, leaving your legs feeling hollow the next day. For multi-day events, training camps, or high-volume double weekends, the post-race meal matters just as much as the loading.

8. Common Failure Modes: It’s Not Just About Not Eating Enough—It’s Also Eating the Wrong Things, at the Wrong Time, with the Wrong Fiber

Failure 1: Rigidly Applying Everyday Healthy-Eating Principles to the 48 Hours Before Race Day

High-fiber vegetables, whole grains, nuts, and legumes are certainly healthy on a daily basis, but if you maintain a very high-fiber intake in the final two days before a race, you’re more likely to have excessive residue in your gastrointestinal tract, frequent bowel movements, bloating, or a heavy feeling in your stomach at the start line the next morning. The priority before a race isn’t “the healthiest” but “what can provide stable energy without causing problems.”

Failure 2: Not Tapering Training, Yet Assuming That Eating More Equals Loading

If you still ride to exhaustion on Friday and do a one-hour run on Saturday, a large proportion of the carbohydrates you consume will simply be used to replenish training losses rather than to create supercompensation. True loading must go hand-in-hand with tapering your training.

Failure 3: Binge-Eating at Dinner While Eating Sparsely During the Day

Glycogen loading depends on the total amount over a 24-hour period, not on winning the dinner battle. Pushing 70% of your carbohydrates into the final meal is the easiest way to cause stomach discomfort, poor sleep, and poor appetite the next day.

Failure 4: Relying Only on Solid Foods and Skipping Liquid Carbohydrates

For heavier athletes, if you completely avoid carbohydrate drinks, it’s usually very difficult to hit your targets. Sports drinks, fruit juice, rice milk, congee, and low-fiber cereals are tools to improve your completion rate, not a shortcut.

Failure 5: No Personalized Gut Training

Concepts like 90 grams of carbohydrates per hour, dual-sugar transport, and gels plus sports drinks are all correct, but if you’ve never practiced them in training, then ramping up the volume on race day itself often results in stomach bloating, nausea, or diarrhea. Your ability to fuel is itself a trainable performance capacity.

9. Individual Adjustments for Cyclists and Runners

Cyclists

• Long climbs and hilly races rely more on high power output than flat cruising, making the value of loading higher.
• Take advantage of the ability to drink on the bike by increasing the proportion of liquid carbohydrates the day before and during the race.
• If the race environment is hot, balance carbohydrate concentration and osmolality; don’t sacrifice your hydration strategy.

Runners

• Due to greater impact and gastrointestinal stress, fiber and fat intake should be even more controlled in the 24 hours before the race.
• If you’re prone to nervous diarrhea, keep your food even simpler after D-1 afternoon, such as white rice, noodles, white toast, bananas, and sports drinks.
• For marathon or half-marathon runners in the faster pace groups, the completeness of your loading often directly determines whether you can hold your pace after the 30-kilometer mark.

10. Conclusion: High-Level Performance Comes from Precise Loading, Not Vaguely “Eating a Bit More”

For endurance events lasting more than 90 minutes, the essence of carbohydrate loading is turning glycogen management into a process that is calculable, schedulable, and verifiable. The most direct evidence supports consuming 10 to 12 g/kg/day of carbohydrates in the 36 to 48 hours before the race. However, considering the typical dietary patterns, work rhythms, gastrointestinal tolerance, and practical feasibility of Taiwanese athletes, extending the strategy to 72 hours before the race at approximately 10 g/kg per day, combined with training tapering, low-fiber and low-fat intake, frequent eating, and liquid carbohydrate tools, is usually easier to execute successfully.

If this article were condensed into a set of execution principles, they would be:

• Calculate your body weight first; don’t eat based on feeling.
• Taper your training first; otherwise, what you eat is just being burned off.
• Take care of your gut first; otherwise, hitting your targets won’t mean you can race.
• Plan your schedule first; otherwise, you’ll end up binge-eating at the last minute.
• Eat before the start, fuel during the race, and replenish afterward.

Truly mature endurance nutrition isn’t about deifying carbohydrates. It’s about knowing when you need high carbohydrate intake, how high it needs to be, how to make your body tolerate it, and finally converting those numbers into performance you can actually use on the starting line.

Related Reading

• 【Sports Medicine】Analyzing Mountain Bike (MTB) and Carbohydrate Loading Strategies: Latest Research and Practical Strategies for a 10g/kg Meal Plan 72 Hours Before Race Day – Toward Sub-3 and Breaking Limits
• Carb-Loading Three Days Before Race Day: Complete Plan and Practical Examples
• Marathon Carb-Loading 3 Days Before: Complete Guide to Food Choices and Portion Calculations
• 14-Day Carb-Loading Template: Filling Your Tank with Carbohydrates