Fueling Strategies to Nutrition Proof Your Ironman

April 15, 2018 0 Comments


“Learning isn’t acquiring knowledge so much as it is trimming information that has already been acquired.” -Criss Jami 

As triathletes progress from sprint and Olympic to 70.3/Ironman, nutrition becomes a major cornerstone of athletic success. 

Athletes scour the internet and pages of magazines for that magical nutrition plan that will catapult their performances onto the podium. 

Let’s state the obvious: there is a lot of information out there. It’s easy to get cluttered or to end up more confused when you began your search.

Unfortunately, there is no one way to eat that will guarantee success. 

On the flip side, athletes are successful on many different diets with many different race day plans. 

So, how do you take all these differing nutrition advice and figure out what works for you? 


Wait, wait, wait…how are you supposed to experiment with 20 to 30 different nutrition companies out there?

You can’t! 

I advise you to pick a few nutrition products and stick with those for one season. Mess around with amounts and timing until you get something that is working for you. 

There is no magical nutrition product, but experimentation can make most products fit your objective. 

In an Ironman, most of the nutrition mistakes you are going to make will happen on the bike, yet the ill effects will show up in the run. 

Because of this, when you are testing race day nutrition programs, you need to run off the bike quite a bit.  

The foundation of all nutrition decisions should be HEALTH. 

Let’s discuss fueling strategies to nutrition-proof your Ironman. 

Pre-Race Eating

Whether you are vegan, paleo, vegetarian, or omnivore you have to limit junk food (think “health”). 

The athlete's body needs veggies for the vast array of micronutrients needed. Quality protein to build strength and balance blood sugar, and healthy fat to feed the brain and hormonal systems. 

However you want to get that accomplished, that should be the cornerstone of your meals.

Good healthy food makes a good healthy body. 

Athletes run into trouble when they forget that we eat for health, not as a reward for training hard, or because their favorite ultra runner is eating that way. 

Beware of junk food disguised as healthy food, most “energy” bars are really candy bars on the inside. 

A good rule of thumb is that you are familiar with every ingredient and would eat each ingredient on its own.

24 Hours Before Race Day

It’s so tempting during a taper period to hit the ice cream, pastries, and coffee shops. 

After all, you have all this time on your hands and you are starting to feel more pep in your step.

Treats are an important part of being a healthy individual, but you want to keep them under control during the 24 hours before your race.

When eating the 24 hours before your race, “Keep It Simple Silly” (KISS)! 

Limit fiber, because although fiber is part of being healthy and “regular” you want to limit any strenuous requirements on the gut leading into a race. 

Some quality protein of your choice and sweet potatoes, with fruit and well-cooked veggies, are all safe bets for pre-race meals. 

Just remember that the foods you choose should be foods you eat regularly. 

Race Day 

When fueling for Ironman races, there are two types of fueling options: 

“All in the bottles”

You really need to know how many calories you need, and you have to make sure the concentration of calories to fluid isn’t too rich or your gut will not process well (poop, puke). 

This is where experimentation is paramount. One con to this method is that when you race in hot conditions you need more fluid. 

But if you combat this by just drinking more of your chosen calorie drink, you up your calories by upping your fluid and you may approach a danger zone. 

Diluting your bottles and drinking more in hot conditions is the best way to get around this. 

A pro to this method is that it’s generally easy to carry and you never have to unwrap anything. 

“Calories in the pocket, fluid in the bottles”

Keep your calories in solid form and your fluid needs in your bottles. 

Use a low-calorie drink, somewhere around 60-70 calories per 22-24oz, and make sure there is a good pairing of electrolytes in there. 

This should be a concentration of drink that you can drink vast amounts of without any gut issues.

So if the weather is hot you can up your fluid intake without gut issues. 

On the solid food side, you want to start with SOLID food and move to less solid food as the race progresses. 


In a 70.3, start with 2 Amrita bars with each bar broken up into 8 pieces (~25 calories each) and then move to cut up citrus fruits.  

In an Ironman start, with 3 Amrita bars and then move to cut up citrus fruits as you get closer to the run.

The cut-up citrus fruits freshen the mouth. What about the run?

A good rule of thumb is to continue with your bike protocol, but cut your calorie load to half. The impact of running requires a lot of blood to be sent to the muscles which leave less for the stomach.

Plus the tummy is bouncing up and down and it just doesn’t work as well under all that stress.

So, keep the calories very absorbable and give it plenty of fluid along the way. 

Also, use Coke only if in dire need. A much better (choose HEALTH) choice is carrying a fuel belt with your chosen fluid and pre-add some green tea extract to your bottles. 

This will provide a more steady caffeine load than Coke, which we all know is not very good for us. This is a good article on how to fuel for the run.


Wading through loads of information out there on the internet is not a substitute for experimentation. 

Your body is your responsibility to figure out and nobody knows you better than you.

Learning more about yourself, your limits, and your lack of limits is what competition and sport are all about.