The Disgust for Sweetness in Ultra-Trail: Strategies to Outsmart Taste Fatigue

Introduction: This Invisible Wall That Doesn’t Come From Your Legs

I still remember that feeling, sharp and burning, as if it were yesterday. It was on the technical trails of the CCC®, around the 70th kilometer. Night was falling, the cold began to envelop me, and my legs, though heavy, were still responding. But another wall, more insidious, was standing before me. An invisible wall, originating not from my muscles, but from my stomach. In my hand, I held an energy gel, a promise of quick fuel. But the mere thought of swallowing that sweet paste made me feel nauseous. My body cried out for food, but my brain screamed: "Never again sugar!". 🤢

This scene, I bet you have experienced it, or you dread it. It’s called "taste fatigue" or, more bluntly, disgust for sweetness. It is one of the most formidable enemies of ultra-trail runners, capable of turning a well-managed race into a true ordeal and leading to withdrawals. It’s not a whim, nor a lack of willpower. It’s a complex physiological and psychological response to extreme stress and monotonous eating.

As a former athlete and sports nutrition enthusiast, I have spent years dissecting this phenomenon. On the field, I tested, I failed, I tried again, and I finally found strategies that work. Today, I want to share with you everything I have learned. No indigestible scientific jargon, just practical advice born from experience, so you can make your nutrition a true ally. Because the goal is to cross the finish line, of course, but it’s especially about enjoying yourself above all, from the first to the last kilometer. And this also involves the pleasure of eating. So, are you ready to outsmart the traps of taste fatigue?

Why Does Your Stomach Say "Stop" to Sweetness? The Behind-the-Scenes of Taste Fatigue

Before looking for solutions, it’s essential to understand what happens in our body and mind after hours of exertion. This rejection of sweetness is not trivial; it’s a warning signal that your body is sending you. Let’s listen to it together.

The Physiological Dimension: More Than Just a Craving

Your body is an incredibly smart machine. When it starts to reject something, it often has very good reasons. In the case of sweetness in ultra, several physiological factors come into play.

1. Flavor receptor saturation: Imagine your taste buds as locks. Every time you eat something sweet, a "sugar" key fits into them. At first, it’s pleasant. But after hours of using the same key, the locks become saturated. The brain, continuously receiving the same "sweet, sweet, sweet" signal, ends up protecting itself by diminishing the pleasant perception or even transforming it into disgust. It’s a defense mechanism to encourage you to seek other nutrients.
2. The digestive system in survival mode: During an ultra-trail, your body is under intense stress. Blood, vital for transporting oxygen, is massively redirected to the working muscles (your legs, your heart, your lungs). The direct consequence: the digestive system is much less perfused. Digestion slows down and becomes less efficient. Simple sugars, like glucose or fructose from gels, are normally absorbed quickly. But when the system is slowed down and bombarded with sugar, it creates a traffic jam. That unabsorbed sugar stagnates in the intestine, ferments, attracts water, and causes bloating, cramps, and nausea. Simply put, your stomach can no longer keep pace.
3. The rollercoaster of blood sugar: Eating only highly sugary products creates insulin spikes and dramatic fluctuations in blood sugar levels. Your energy skyrockets, then plummets just as quickly, leaving you drained and searching for another sugar "hit". Over time, this cycle is exhausting for the body, which instinctively will start asking for more stable nutrients (fats, proteins, complex carbohydrates) to break free from this vicious circle. Rejecting sweetness is also a call for more stability.
4. Electrolyte imbalance: When you sweat, you don’t just lose water. You lose essential minerals, especially sodium (salt!). A sodium deficiency can interfere with taste perception and make sweet flavors even more nauseating. Your body, in its great wisdom, then develops a strong craving for savory to address this deficit. This is not a craving; it’s a vital need!

The Psychological Dimension: When the Mind Gets Involved

Ultra is 50% in the legs, 50% in the head. Nutrition is no exception. Disgust for sweetness is also a deeply psychological phenomenon.

• The negative association: It’s the famous Pavlov reflex. After 10, 15, or 20 hours of effort, muscle pain, and intense fatigue, if at every difficult moment you have swallowed a gel, your brain will end up making an association. Sweet taste = suffering. The mere smell or sight of a gel can then trigger an almost instantaneous rejection reaction. Your mind seeks to protect you from what it now associates with a negative experience.
• Lassitude and the need for comfort: Eating the same thing for an entire day is deadly monotonous. Humans are omnivores who need variety, different textures, and flavors. In an ultra, morale is an essential component of performance. A comforting food, like a bowl of hot soup in the middle of the night or a piece of familiar-flavored cheese, has immense psychological power. It breaks the routine, provides simple and authentic pleasure, and gives you the mental strength to continue. Sweetness, often artificial and chemical, rarely offers this comfort.
• Listening to your body's signals: This disgust might be the most important signal your body can send you. It’s not telling you "stop eating"; it’s saying "give me something else". Learning to interpret these signals rather than fight them is one of the keys to success in ultra. If you dream of a salty pretzel, it’s probably because your body urgently needs sodium. If you fantasize about an avocado, it might be that you are missing healthy fats. It’s an intimate conversation between you and your physiology.

Anticipate to Avoid Enduring: Keys to Outsmart the Sweet Trap

The best way to manage taste fatigue is to ensure it never appears. This requires a bit of preparation, but I promise you it’s worth it. A well-structured nutritional strategy is as important as your physical training.

Test, Test, and Test Again During Training

This is my golden rule, one I repeat endlessly: NEVER, EVER, TRY ANYTHING NEW ON RACE DAY. Whether it’s shoes, shorts, or a new exotic flavor gel. Your stomach is even more sensitive than your feet to novelties under stress conditions.

• Simulate race conditions: Take advantage of your long runs to test your protocol. Not just a 1.5-hour run. I’m talking about real long runs, those of 4, 5, 6 hours or more. This is when the digestive system starts to be put to the test. Eat and drink exactly as you plan to do during the race. Test at different paces and on different elevations. Do a long run starting at 4 AM to see how your body responds to a pre-race breakfast. Do a night run to test your nutrition in the cold and fatigue.
• Build your "flavor library": As you test, note everything in a notebook. Brand X gel, flavor Y: went well. Brand Z applesauce: too acidic. Mini ham-butter sandwich: perfect after 3 hours. The goal is to create a list of "approved" sweet and savory foods that you know you can rely on. This list will be your best friend on race day.
• Train your digestive system (the famous "Gut Training"): Yes, the stomach can be trained! Studies, like those conducted by Asker Jeukendrup, a pioneer in sports nutrition, have shown that you can train your digestive system to tolerate larger amounts of carbohydrates per hour. This involves regularly consuming carbohydrates during your training to improve gastric emptying speed and intestinal absorption capacity. Start with small amounts (30g/hour) and increase very gradually over several weeks. You’ll be surprised to see how adaptable your body can be.

Build a Varied and Flexible Nutrition Plan

The key to success is VARIETY. Your nutrition plan should not be a list of gels, but a symphony of flavors, textures, and temperatures.

1. The sweet/savory alternation FROM THE START: This is the most common mistake. Many runners wait until they are nauseated by sweetness to switch to savory. It’s too late! The damage is done. You need to start alternating from the first or second hour of the race. The principle is simple: one sweet intake, one savory intake. Or two sweet intakes, one savory intake. Find the rhythm that suits you.
2. A concrete example of a plan for the first 4 hours:
   • Hour 1: 1 classic energy gel + a few sips of water. It’s the beginning, the digestive system is still fresh.
   • Hour 2: Half a salty cereal bar (like almond-sea salt) or 2-3 crackers like TUC + low-sugar electrolyte drink.
   • Hour 3: 1 fruit compote (apple or banana, low acid) + a handful of salted cashews. We’re providing "natural" sugars and healthy fats.
   • Hour 4: It’s time for a more substantial snack. A small salted sweet potato mash (in a soft flask) or half a sandwich made with soft bread and fresh cheese.
   This is just an example, to be adapted to your tastes. But you see the idea: we vary the carbohydrate sources, flavors, and textures.
3. The power of textures: Think about varying pleasures in your mouth. Alternate liquid (drink, soup), semi-liquid (gel, compote, puree), soft (soft bread, rice cakes), and crunchy (pretzels, crackers, chips). This sensory stimulation helps combat fatigue and makes eating much more enjoyable.
4. Plan Based on Aid Stations: Before the race, study the profile and list of foods offered at each aid station. It’s a gold mine. Identify where you can find broth, pasta, cheese. This way, you can plan to eat your personal solid foods between stations and enjoy the "fresh" and often warm food from the aid stations. Knowing that a bowl of hot noodles awaits you in 10 km can be a tremendous psychological boost!

Salt, Your Best Ally: An Arsenal of Tasty and Effective Options

Okay, we understand that we need to eat savory. But what, specifically? Gone are the days of just a quarter of an orange and a TUC. The options have expanded, and homemade is king. Here are my favorite options, tested and approved on the field.

Must-Haves to Pack in Your Bag

These foods are easy to prepare, transport, and digest. They will quickly become your best adventure companions.

• Homemade savory purees: This is my secret weapon! Easy to swallow, even when chewing becomes difficult, they are an incredible source of energy. My favorite recipe: a sweet potato, a carrot, a drizzle of olive oil, a good pinch of salt. Steam cook until tender, blend with a bit of cooking water until you achieve the desired consistency. You can even add a touch of cumin or half a portion of soft cheese like Kiri for more indulgence. Pour into a reusable soft flask, and you're done. Energy, vitamins, electrolytes. Simply perfect. 🍠
• Mini sandwiches or wraps: Soft bread without crust is your friend as it’s highly digestible. Lightly fill it with white ham, turkey, soft cheese, hummus, or almond butter with a pinch of sea salt. Cut it into four, wrap it in plastic film. It’s a real comforting meal in pocket format.
• New potatoes: Boil or steam them with their skins, then roll them generously in salt. Let them cool and put a few in a small freezer bag. They are a carbohydrate and potassium bomb, and the salt that crunches under your teeth is pure bliss.
• Salty rice cakes (like athlete's “rice cake”): Inspired by cycling pros. Cook sticky round rice (like risotto or sushi rice) until very sticky. Add grated parmesan, diced ham, or even chopped olives. Press everything into a dish, let it cool, and cut into small bars. It’s delicious and filling for a long time.
• Dry snacks: Pretzels, crackers, breadsticks... They are perfect for crunchiness and salt intake. Also consider salted nuts: cashews, pistachios, almonds. They provide fats, a source of energy for very long durations. Be careful not to overdo it, as they can take longer to digest.

Make the Most of Aid Stations During the Race

Aid stations are oases. Don’t just go for the TUC and bananas. Look for salty treasures.

• The magic broth: If there’s one thing you should never miss at an aid station, it’s vegetable or chicken broth. In the middle of the night, when it’s cold and you’re tired, a cup of hot broth is a resurrection. It warms you, hydrates you, provides sodium, and calms the stomach. Don’t hesitate to dip a piece of bread in it.
• Vermicelli soup or instant noodles: More and more races offer this at base camps. It’s the holy grail for ultra-trailers. Carbohydrates, salt, warmth, comfort. If you have a drop bag, putting a portion of freeze-dried noodles in it is an excellent idea.
• The cheese-salami duo: Consume in moderation as fat slows digestion, but a small piece of Comté or a thin slice of salami can really boost your morale. The taste is intense, satisfying, and it’s a real break from bland or sweet flavors.
• Don’t forget the bread: A simple piece of plain baguette can be enough to "clean" your palate and calm a rising nausea. It’s neutral, easy to digest, and prepares the stomach to receive something else.

Don’t Panic: How to React When Nothing Goes Down?

Despite the best preparation in the world, a crisis can happen. The stomach ties up, nausea rises, and even water seems difficult to swallow. Above all, don’t panic. There is an emergency protocol to handle the situation and get back on track.

Step 1: Take a Break and Don't Force

It’s counterintuitive; you want to move forward. But forcing yourself to eat or drink when your body says no is the worst thing to do. You risk vomiting and further dehydrating yourself. So, we apply the gentle method:

• Stop everything. Sit at the side of the path or at the next aid station. Sit down for a few minutes.
• Don’t eat ANYTHING for at least 20 to 30 minutes. Let your digestive system rest. This is the top priority.
• Focus on your breathing. Slow, deep inhalations through the nose, long exhalations through the mouth. This helps calm the nervous system and reduces the sensation of nausea.

Sometimes, this simple pause is enough to get everything back in order. It’s an investment of a few minutes that can save you hours of hardship. Enjoying yourself above all also means knowing when to stop and listen to yourself.

Step 2: Reset the Palate and Stomach

Once the nausea has subsided a bit, the goal is to start again on solid ground. You need to "wash" away the bad sensations.

• Rinse your mouth. Take a small sip of water, swirl it around your mouth, and spit it out. Repeat two or three times. This eliminates the sweet and acidic aftertaste.
• Drink clear water in small sips. A sip every 5 minutes, no more. If that goes well, you can try sparkling water (some find that bubbles help calm the stomach) or water with a slice of lemon.
• Try a "taste reset". Chewing a strong mint gum or a mint tablet can help. Ginger is also an excellent natural anti-nausea remedy. Having some candied ginger can be a lifesaver.

Step 3: Reintroduce Food Very, Very Gradually

If water goes down well and you feel a bit better, you can attempt to eat again. But proceed with extreme caution, as if you were learning to eat again.

1. Start with savory liquid: The first thing to try is a clear, warm broth. It’s the perfect transition. It’s hydrating, savory, and gentle on the stomach.
2. Move to neutral, dry solid food: If the broth goes down well, wait 15-20 minutes and try something very simple. A plain cracker, a TUC, or a small piece of bread. Eat it very slowly, chewing thoroughly.
3. Listen to your real cravings: It’s often at this point that the body sends a very clear signal. If an irrepressible urge to have vinegar chips hits you, it might be exactly what you need (salt + acidity). Trust your instinct; it’s often wiser than any theoretical plan.
4. Gently return to your plan: Once you’ve managed to eat something savory, you can gradually reintroduce your alternate plan. Perhaps with a compote (acidic but natural) before trying a gel much later.

These crises are often the result of upstream mistakes and an accumulation of small disruptions. To avoid getting to that point, I invite you to read my article on the 5 mistakes of aid stations to never make on Ultra-Trail, it’s a good addition to solidify your strategy and understand how prevention is your best weapon.

Conclusion: Nutrition, an Adventure Within the Adventure

Disgust for sweetness is not a fatality. It’s a challenge, a riddle that every ultra-trail runner must solve for themselves. There is no universal magic formula, but fundamental principles that, once mastered, radically change the experience of the race. ✨

Remember these key points:

• Anticipation is key: Everything happens during training. Test, try, and note what works for YOU.
• Variety is your best weapon: Alternate between sweet and savory from the start of the race. Also think about textures and temperatures.
• Salt is your savior: Integrate homemade savory options or smartly take advantage of aid stations to break the monotony of sugar.
• Listen to your body: A craving or disgust is a message. Learn to decode it rather than combat it.

Ultimately, managing your nutrition in ultra is like managing your race: it requires a solid plan, but also the ability to adapt, improvise, and remain humble in the face of the signals that the mountains and your body send you. Every race is an open-air laboratory, an opportunity to learn more about yourself.

So, be curious, experiment fearlessly in training, and build the strategy that will allow you to move forward with energy and a smile, even when the night is dark and the finish line is still far away. That’s the true victory: finishing the adventure with the feeling of having been a good partner to yourself. Safe travels and enjoy your meals on the trails!