The Nutrition Game of Running 100 Miles

This month we continue athlete and certified UESCA ultra-running coach Laurel Walker's multi-part 'Coach's Corner' series on running 100 Mile races. In this instalment, Laurel (below) discusses the fuelling/nutrition side of taking on a Miler.

There’s a joke in the ultra-running community that running an ultra is an eating contest with some running mixed in. Despite this being a joke, there is some validity to the fact that the more calories you are able to get, the better you will feel. 

One of the best analogies I’ve found is thinking of fuelling for an ultra in the same way you’d approach fuelling your car on a road trip. Just like you would fill up your tank when it gets low, and ideally before the light turns on, you need to be refilling your “tank” with calories. And just like filling up before you see the light turn on, you should get ahead of the “light” turning on. With running this could mean feeling tired, sad (this might sound strange but if you are sad, you probably need calories!), low energy or dizziness, all of these can indicate that you are behind on calories and it is much harder to catch back up if you are already in or approaching a deficit. 

Early and often is the key when it comes to fuelling for a long effort, I suggest every 30 minutes as this works well for me. Don’t wait until you are hungry or thirsty, that means you are already in the hole. 

Everyone is different in terms of calories, water, carbs, and sodium per hour, but here is a place to start based on my experience:

Fueling guidelines (per/hour):

Water: 1 Liter

Carbs: 50-60g

Sodium: 500mg

Calories: 250-300 as a minimum 

When we run, blood flow is directed away from our stomach to help our muscles work, which can make digestion harder. Hydration can help with this so being on top of that is key. Generally if it is hot and dry, you will need more water and sodium/electrolytes. It can also be much harder to get calories in without feeling sick if it is hot so make sure you practice this. Carbs are king when it comes to endurance sports so, again, practice, practice, practice! Fuel with them on shorter efforts in training just to get your body used to processing. And, experiment with different types of fuel. I am a huge fan of Skratch Fuel and Hydration (not sponsored). 

Fuelling through the night

More often than not we are running overnight during a 100 miler. When your body is tired and wants to sleep, taking in calories can be really hard. My advice and what works for me? Slow the pace, take in salty calories like broth, ramen noodles, salted mashed potatoes, quesadillas, etc., and trust that when the sun rises you will feel better. 

What do you do when your body rejects everything?

Don’t get discouraged if your body rejects calories and/or you feel really sick, this is normal and you will get through it. Ginger chews, ginger ale and potatoes can help soothe the stomach and get you back on track. Take it in stride and keep moving forward. 

Fuelling is personally my biggest puzzle when it comes to running 100 miles, so don’t be discouraged if you don’t nail it on the first try! I’ve been running ultras for over a decade and I’m still working on the puzzle. Just make sure you practice as much as possible and don’t try anything new on race day, if you can help it. Have fun out there and enjoy the eating contest!