Q&A with ultrarunner Juuso Simpanen: Fueling for Ultra-Running Success

Q&A with ultrarunner Juuso Simpanen: Fueling for Ultra-Running Success

Finnish former footballer Juuso Simpanen is a rising star in the ultra-running world.

His debut in the Ultra-Trail du Mont-Blanc last year, regarded as the most competitive trail ultramarathon in the world, saw him record the best-ever time for a Finn in the event. He has also won the Ultra Trail Tour Finland twice during his ten-year running career.

But ultra-running is a process, and there is always something you can improve. Looking to emulate the international success of Spain’s Kilian Jornet and Frenchman Mathieu Blanchard, Juuso is working hard on ‘nailing the fuel strategy’ so he can race against the best in the world and win.

To gain an insight into how he will achieve that goal, we sat down with him to talk about gut training and fuelling.


Why is gut training necessary for ultra-runners?

When you don't eat enough during an ultra-run, your muscles stop working correctly, you may stumble, and your pace slows a lot. When those negative thoughts begin, you haven't eaten enough. Eating a lot before an ultra-race is essential, but carb loading is unnecessary because you burn your stored glycogen after 2-3 hours—it’s more important what you take during the race.

When I began gut training, I suffered from stomach pains and diarrhea after trying to go too high, too fast. In my first race, I averaged about 40 grams of carbohydrates per hour, and now 100 grams per hour is good, which is a lot if you are unused to it. It's vital to practice fuelling during your training.

Over the past year, however, I’ve had problems, and I'm not where I want to be. I’ve managed 70-80 grams of carbs per hour, so my goal is to train back to at least 100 grams per hour during a 20-hour race.

Another struggle is consuming sweet items, especially after consuming sugary energy products every 15-20 minutes for 10-15 hours. I find neutral or slightly salty energy products to be a great alternative. In upcoming races, I plan to incorporate neutral-flavored options right from the start, allowing me to consume more carbohydrates.

Now that you are training to accomplish that, what does a typical training day menu involve?

I start the day with fruit, maybe a banana, because I train better without too much food in my stomach. After the workout, I have a fruit and vegetable smoothie and take a Nosht chocolate-flavored recovery mix. A balanced meal or snack containing protein and carbs within the ‘golden hour’ after a workout enhances recovery and promotes muscle growth. In the afternoon, I snack on nuts, fruits, or vegetables. Dinner is my biggest meal, including pasta, rice, potatoes, tofu, lentils, and veg.

Because I’m vegan, I take a B12 vitamin tablet daily and an iodine tablet weekly since I don't eat fish. We don't get much sunlight in Finland during the winter, so I also take vitamin D. While not a regular practice, I occasionally take iron as a precaution against foot strike hemolysis, sweat loss, and increased hepcidin levels.


When do you begin to prepare for an ultra-marathon, and how does your training regime change?

The two months before a race, I run the most kilometers—between 200-250 kilometers per week. During that period, I do two long (40-80 km) runs a week, along with fast repeats or a tempo run (20-30k) once a week. At least once a week during the long runs, I practice the fuelling strategy to get as much energy as I take during the race.

I take a sports drink or a couple of gels during tempo runs to keep going. I don't focus on fuelling that much during easy runs or hard workouts like tempo runs or repeats– it is just before and after.

What are your go-to fuelling products during training and an ultra-race?

Nosht, my sponsor, has been my go-to fuel for three years. They have energy chews, which I often eat, and gels and drink mixes. While I do ingest mostly fluids and gels during 100k and 100-mile races, it is a little different when you run longer races.

During races, I incorporate caffeine as a performance enhancer. For a 20-hour race, I begin consuming small amounts of caffeine after approximately 10 hours. However, I avoid using caffeine during training as it slightly disrupts sleep. The caffeine also provides an additional boost towards the end of a race.

It's good to take on more solid foods once every two or three hours because your pace and heart rate are much slower, and it makes the stomach feel a little better. I eat small amounts of easy-to-digest white bread, potatoes, oatmeal, and nutrition bars.


Hydration is vital in ultra-running; what are your strategies to prevent dehydration?

I drink a liter of water in the morning to get the system right after sleeping. After every run, I drink at least another liter. During the summer, I take water when running and try to get between 0,5 liters per hour or even a liter if it’s hot. Sodium intake is also essential, so I aim for at least 500 milligrams per hour, which increases to 800 if it's hot and humid. If you’re dehydrated, it's hard to digest the fuel.

I have yet to rely on sodium/electrolyte capsules or tablets, but they can be helpful when primarily consuming water. I ensure that my energy products contain sufficient electrolytes to meet my needs.

How do you recover and transition back into training after completing an ultra-marathon?

The first day after a race can be difficult for the gut, but after a good night’s sleep and rehydration, I'm hungry and eat a lot. Supplements and recovery drinks don’t play much of a part after the race because I want regular food.

During the first 5-6 days, however, I don't run at all. It's easy walking and cycling, and then I start with leisurely one-hour runs. In the third week, I begin more challenging workouts, such as an easy tempo run, so 40-60 minutes. If all goes well, regular training resumes in the fourth week.

Finally, any advice for runners preparing to run their first ultra-marathon?

Practice fuelling during training a lot because it's essential to get it right. Don't try anything new during the race. Stick to the plan.

Ready to fuel your ultra-running journey? Take inspiration from Juuso Simpanen's strategies and incorporate them into your training regimen. Remember, practice makes perfect. Train hard, fuel smart, and unleash your potential. Begin your adventure by booking a free fueling coaching!

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