What to Eat the Week of a Triathlon for Peak Performance

December 23, 2025 •

4 min read

According to sports nutrition experts, maximizing your muscle glycogen stores can improve endurance performance by 2-3%. This crucial energy optimization is achieved through a disciplined dietary approach in the days leading up to your event. Knowing what to eat the week of a triathlon is essential for every athlete looking to cross the finish line strong.

Quick Summary

A proper race week nutrition plan emphasizes increasing carbohydrate intake while tapering training to maximize muscle glycogen stores. It involves reducing fiber, moderate protein, and low fat, sticking to familiar foods, and prioritizing hydration to prevent gastrointestinal issues and ensure the body is fully fueled for race day.

Key Points

Start early in the week with balanced meals: Use the early taper days to eat nutrient-dense foods including complex carbs, lean protein, and healthy fats before shifting to a higher-carb, lower-fiber focus.
Prioritize easily digestible carbohydrates 36-48 hours pre-race: Switch from whole grains to simple carbs like white rice, pasta, and bread to maximize glycogen stores without digestive distress.
Cut back on high-fiber foods: Tapering high-fiber items like certain vegetables and legumes in the final days helps prevent unwanted gastrointestinal issues during the race.
Stick to familiar foods and fluids: Never try new food or hydration products on race day. What you practice in training is what you execute on race day.
Stay consistently hydrated: Sip fluids throughout the entire race week. Glycogen is stored with water, and maintaining hydration is critical for optimal fueling.
Manage portion sizes, especially dinner the night before: Eat your largest carb-heavy meal at breakfast on the day before the race. The final dinner should be light and early.
Expect temporary weight gain from water retention: The 1-2kg weight increase from glycogen and water storage is normal and a sign of proper loading. Do not let it concern you.

Your Week-Long Triathlon Nutrition Strategy

Your race-day performance is heavily influenced by your nutrition in the preceding days, not just the final meal. The goal is a gradual shift towards carbohydrate-heavy, easily digestible foods to build your body's energy reserves without causing discomfort. This approach is often called carbohydrate loading, but it's more about strategic adjustments than mindless gorging.

Monday to Wednesday: The Balanced Approach

Early in the week, your focus should be on nutrient-dense, balanced meals to support your final, lighter training sessions.

Complex carbohydrates: Include foods like brown rice, oats, and quinoa. These provide sustained energy and essential vitamins.
Lean protein: Eggs, chicken, fish, and tofu are excellent sources to aid muscle repair and keep you feeling full without weighing you down.
Healthy fats: Moderate amounts of avocados, olive oil, and nuts are beneficial for overall health.
Hydration is key: Maintain consistent fluid intake. Your body needs water to store glycogen effectively, so drink consistently throughout the day.

Thursday to Saturday: The Carb-Load Phase

As the race approaches, your strategy shifts to maximizing carbohydrate storage. This is when you begin the true 'loading' phase, typically 36–48 hours before the event.

Start reducing fiber: High-fiber foods, such as beans, broccoli, and whole grains, can cause gastrointestinal distress on race day. Gradually swap them out for lower-fiber, easily digestible alternatives.

Focus on simple, familiar carbs: These are easier for your body to process and convert to glycogen quickly.

White bread and pasta
White rice
Peeled potatoes
Bananas
Low-fiber cereals

Maintain hydration: Continue sipping on water or electrolyte drinks. Do not chug large quantities right before the race, as this can lead to bloating and an electrolyte imbalance.

Weight gain is normal: Expect a temporary weight gain of 1-2kg due to the water your body holds with stored glycogen. This is a positive sign that you are well-fueled.

Race Day Minus One: The Final Polish

Biggest meal in the morning: Eat your largest carbohydrate-rich meal early in the day, like a big breakfast. This gives your body plenty of time to digest.
Light, low-fiber dinner: Your last dinner should be your lightest meal. Choose a small portion of white rice or pasta with a light sauce and lean protein. Eating an early dinner (5-6 PM) and going to bed with a slightly empty feeling can help you sleep better.
Hydrate steadily: Keep sipping fluids, including a sports drink, to ensure you are well-hydrated going into the night.

Race Day: The Final Fuel-Up

Stick to foods you've tested in training. No surprises!

Breakfast 3-4 hours prior: Have 400-600 calories of easily digestible, carbohydrate-rich foods. Think oatmeal, a bagel with a thin layer of nut butter, or rice cakes.
Sip fluids: Continue to sip on sports drinks to top off glycogen stores and maintain hydration until the race starts.
Final snack: A small, quick-acting carbohydrate snack like an energy gel 30 minutes before the start can provide a final boost of energy.

Comparison of Pre-Race Week Nutrition


Aspect	Early Race Week (Mon-Weds)	Final 48-72 Hours (Thurs-Sat)	Race Day Minus One	Race Morning
Carbohydrates	Balanced mix of complex carbs (whole grains, sweet potatoes).	High intake, focusing on simple, low-fiber options (white rice, pasta, bread).	High carb breakfast; moderate carb lunch; light, low-fiber dinner.	Easily digestible, low-fiber carbs (oatmeal, bagel, rice cakes).
Protein	Moderate amounts of lean protein (chicken, fish, legumes).	Moderate amounts, but reduce to make room for increased carbs.	Small portions of lean protein.	Minimal, to prevent digestive issues.
Fat	Healthy fats in moderation (avocado, nuts, olive oil).	Minimal fat intake.	Very low.	Very low.
Fiber	Normal, healthy fiber intake from fruits and vegetables.	Gradually decrease high-fiber foods to minimize digestive stress.	Low-fiber foods only.	Very low-fiber foods only.
Hydration	Consistent fluid intake throughout the day.	Consistent sipping of water and electrolyte drinks.	Steady intake, avoiding large volumes just before bed.	Sip sports drinks and water up to race start.
Purpose	Support training and recovery.	Maximize glycogen stores.	Final glycogen top-off; easy on digestion.	Provide immediate energy; restore liver glycogen.

Conclusion: Practice Makes Perfect

The nutritional strategy for the week of a triathlon is a carefully orchestrated sequence of tapering your training while gradually shifting your diet to prioritize high-glycogen, low-fiber foods. The objective is to stand on the starting line with energy reserves at their maximum, your stomach settled, and your body optimally hydrated. This is not the time for experimental foods or sudden changes. The most important rule is to use only the foods and drinks you have successfully tested during your long training days. A well-executed nutrition plan provides a powerful psychological boost, ensuring you are mentally and physically prepared to perform your best on race day. The discipline you apply in your final week's eating will pay off in every stroke, pedal, and step toward the finish line.

For more detailed meal planning examples and insights, sports nutrition departments at reputable institutions like Hôpital de La Tour can offer personalized guidance.

Frequently Asked Questions

The main goal is to maximize your body's muscle glycogen stores, which serve as the primary fuel for endurance events. This is done by strategically increasing carbohydrate intake while decreasing training volume.

Reducing fiber intake in the final 48-72 hours helps minimize bulk in your digestive system, reducing the risk of bloating, cramping, and needing a mid-race bathroom break.

Yes, a temporary weight gain of 1-2kg is completely normal and expected. This weight is due to the water that is stored along with the glycogen in your muscles and will be used for fuel during the race.

Your dinner should be a moderate, low-fat, low-fiber meal rich in easily digestible carbs. A simple example is a moderate portion of plain pasta or white rice with a light, tomato-based sauce and a small piece of lean chicken.

You should aim to eat your pre-race breakfast 3 to 4 hours before the race start. This allows sufficient time for digestion and for your body to absorb the necessary fuel.

Common mistakes include trying new foods on race day, over-hydrating right before the event, under-fueling long training sessions, and failing to have a well-practiced race nutrition plan.

Hydration is crucial as it helps your body effectively store glycogen. Consistent sipping of water and electrolyte drinks throughout the week ensures you start the race well-hydrated and ready to perform.