Preparing for a 100K ultramarathon requires careful nutritional planning, which is just as vital as physical training. While the body has fat reserves, its glycogen (carbohydrate) stores are limited, typically lasting only a couple of hours during intense activity. Strategic carbohydrate intake before the race is crucial for maintaining energy and preventing fatigue. The aim is to start the race with maximal glycogen stores and a settled stomach.
The Pre-Race Carb-Loading Phase (2-3 Days Before)
Effective carb-loading involves increasing carbohydrate intake over two to three days while reducing fat, protein, and fiber. Aim for 8 to 12 grams of carbohydrates per kilogram of body weight daily. To manage this intake without feeling overly full, focus on easily digestible, low-fiber sources.
Practical Carbohydrate-Loading Tips
- Frequent Eating: Consume smaller meals and snacks throughout the day.
- Include Liquid Carbs: Incorporate juices, smoothies, and sports drinks.
- Limit Fiber and Fat: Temporarily decrease high-fiber foods and fatty meals.
- Prioritize Hydration: Maintain hydration by regularly drinking fluids, potentially adding electrolytes.
The Final 24 Hours: Light and Familiar
In the day before the race, focus on light, easily digestible foods you've eaten before. Avoid new foods or heavy spices.
Meal Ideas for the Final Day
- Breakfast: Oatmeal or porridge with dried fruit and a touch of honey.
- Lunch: White rice with lean protein like chicken or fish.
- Dinner: Plain pasta with a simple tomato sauce or a bagel with peanut butter and banana.
Race Morning: The Last Fuel Top-Up
Eat your race morning meal 2 to 3 hours before the start. It should be small, high in carbohydrates, and low in fiber, protein, and fat for easy digestion.
Reliable Race Morning Breakfast Options
- Bagel with honey or jam.
- Oatmeal with banana and nut butter.
- White rice with a touch of honey.
- Toast with jam.
- Smoothie made with fruit, oats, and plant-based milk.
The Final Hour: Quick Energy Boost
Around 30-60 minutes before the race, a small, simple carbohydrate snack can provide a quick energy lift.
- Energy gel or chews.
- A few dates or raisins.
- Small banana.
Hydration and Electrolyte Strategy
Consistent hydration is crucial for a 100K. Ensure you are well-hydrated in the days leading up to the race and continue to hydrate with electrolyte drinks.
Comparison of Pre-Race Fueling Strategies
| Feature | Carb-Loading (2-3 Days Out) | Race Morning (2-3 Hours Out) | Final Hour (30-60 Mins Out) |
|---|---|---|---|
| Carbohydrate Goal | 8-12 g/kg body weight | 1-4 g/kg body weight | ~30 grams |
| Macronutrient Balance | High carbs, low fat/protein/fiber | High carbs, low fat/protein/fiber | High carbs, minimal fat/protein |
| Food Type | Lower fiber grains, starches, fruits, liquid carbs | Easily digestible, low-fiber carbs (toast, bagel, oats) | Simple sugars (gels, chews, dates) |
| Purpose | Maximise muscle and liver glycogen stores | Top off remaining glycogen and settle the stomach | Provide a final blood sugar boost |
| Hydration | Consistent hydration with electrolytes | Drink 5-7 ml/kg fluid; consider electrolytes | Sip water or electrolyte drink |
Troubleshooting: Avoiding GI Distress
Ultra-distance running can stress the digestive system.
- Practice in Training: Always test your planned race nutrition during long training runs.
- Small, Frequent Intake: During the race, consume small amounts of fuel frequently.
- Vary Flavors: Combat palate fatigue by alternating between sweet and salty food choices.
- Address Issues Quickly: If GI problems arise during the race, try slowing your pace and cooling down.
- Consider Ginger: Some runners find ginger helps with nausea.
Conclusion: Fuel Your Victory
Successful 100K running depends heavily on proper nutrition starting days before the race. By implementing a diligent pre-race fueling strategy, you can maximize your energy stores and reduce the risk of digestive problems. Remember that individual needs vary; personalize your plan based on what you've successfully practiced during training. A well-fueled runner is better prepared to tackle the challenges of a 100K ultramarathon.
