10 Foods To Fuel an Ultra Marathon

Best Ultra Running Foods

There’s nothing quite like a fuelling foul up to wreck your chances during an ultra marathon. There’s the obvious bonking perils that come from not eating enough, the risk of tummy-turmoil from eating on the move, not to mention the toilet-related dangers of swallowing a dozen carb gels on the bounce. The fact is, topping up your fuel tank during an ultra run is a tightrope walk and it can be hard to find the best ultra running foods for you.

It’s not just choosing what to eat that makes race nutrition hard to get right, the conditions play a part too. Heat, altitude, incline all affect the level of intensity you’re working at, which in turn alters your heart rate, sweat rate and salt levels. Why does this matter? Well the higher your heart rate, the more likely you are to be burning carbs as a main fuel source and so the need for readily-available carbs increases. And the more you sweat, the more hydration plays a role in how you feel physically and what you can stomach.

So what the best approach to ultra nutrition? There’s plenty of wisdom out there and two of pieces of advice I’ve seen repeated most often, that make most sense to me, are this:

1. Eat early and eat well: The idea here is that the longer the race goes on and the more pressure your system is under, the harder it can be to eat, so filling the tank early while you feel stronger seems sensible.

2. Eat little and often: giving your stomach smaller, regular amounts of food to deal with should reduce the risk of digestive issues. It can also help keep blood sugar levels more stable and reduce your chances of bonking.

Why is it harder to digest food while you run?

While you’re running, your visceral blood flow decreases with somewhere close to 88 per cent of blood diverted away from the gastrointestinal tract towards those blood hungry muscles that are doing all the work. That means there’s less of the blue stuff heading to the stomach to help with the absorption of the water and that flapjack you just ate. Essentially your body prioritises your intense exercise effort over the digestion process and that can lead to nausea, the feeling that food is just sitting in your gut, reflux, runny runners’ bum and all sorts of other nasties.

What are the best ultra running foods to eat during a race?

The most important piece of advice I can offer is to eat whatever works for you. Trial and error is essential. Show me an ultra runner and I’ll show you someone who’s come a cropper after eating something that seemed like a good idea at the time but ten minutes later has joined the One Sock Brigade. Just like everything else in this game, one person’s meat is another’s poison.

That said, you can learn from others. And I have a few principles I try to follow.

  1. Drink your energy: I like to carry a source of liquid fuel because it’s easy to absorb and you are in control of your fuel rather than having to wait for aid stations.
  2. Go as natural as you can.:My powdered fuel contain no nasties and the rest of the things I eat are all 100 per cent natural, simple foods.
  3. Eat before you think you need to: If you wait until you feel like you’re running on fumes then you’re risking dropping into that situation where you feel nauseous and can’t face eating but it’s absolutely what you need to do to clear the sickness.

With that in mind, here’s what you’ll find in my bag for The North Face Lavaredo Ultra Trail, the Centurion Running Thames 100 and Dixons Carphone Race to the Stones.

Best Ultra Running Foods: On the Move

Generation UCAN

An alternative to Tailwind, Generation UCAN is a powdered energy drink with SuperStarch, a complex carbohydrate (derived from non-GMO corn). It comes in a portable sachet that’s easy to add to a 650ml bottle and it’s main benefits are that it stabilises blood sugar and causes virtually no reaction from the fat-storage hormone insulin. So no sugar spikes, just nice even fuelling by the mouthful. There are a range of flavours such as tropical orange and pomegranate and blueberry, all of which taste ok, although after 14 hours can become a bit icky.

Poliquin RISE

Another powder I add to the same 650ml bottle of water along with Generation UCAN, Poliquin Rise contains a range of nutrients that support the body’s ability to adapt to the biochemical requirements necessary for increased performance. It promotes hydration, nutrient balance, protein anabolism, and pH balance, all of which help to maintain focus and sustained energy levels. It’s sweet to taste but isn’t quite as sickly as some sugary drinks and along with UCAN, when sipped at regular intervals helps provide a consistent, even source of energy. No nasty sugar spikes that you can get from eating a gel or glugging flat coke.

33Shake Gels

I don’t think I’ve ever met anyone who actually likes the taste of the chemical goop carb gels pumped out by most of the familiar brands. I’m looking at you Gu, Isotar and Co. 33Shake gels are different. Fresh, handmade and made entirely from natural ingredients, theses are the first gels I’ve found that I actually look forward to eating. The mix of whole, unprocessed chia seeds, Himalayan salt, low-GI sugars, Omega-3s and antioxidants delivers a hit of 90 calories from one gel.


The supreme athletes who regularly smash the Sahara and pick up the podium spots at the Marathon Des Sables often run on a diet of dates. These little dried delights are full of natural sugars and each one packs a 20 calorie punch, without any of the chemical nastiness you get with sweets or endurance beans. What’s more they’re easy to carry and, for me at least, easy to stomach. I used them during the Centurion Running Thames Path 100 to great success and so I’ll be carrying three for every hour of running.

Ella’s Kitchen Fruit Pouches

Basically squished up pureed fruit combos in a really convenient pouch with a resealable lid, I first discovered Ella’s Kitchen fruit pouches thanks to my 2-year-old son. A regular in his snack back, they’re a fantastic hit of fresh, tasty, tummy-friendly calories. I recommend The White One and The Purple One.

Whole Earth Power Balls

From the brand behind the tasty, organic nut butters these Whole Earth Power Balls are fairly new to my running pack. There’s no rocket science here, just half a dozen good, energy-rich natural ingredients squished up and rolled into snackable balls that pack around 40 calories and 4.4g of carbs. Ingredients includes pumpkin, chia and flax seeds, goji berries and coconut mixed with Whole Earth’s gluten-free peanut butter, which also steers clear of environmentally harmful palm oil.

Best Ultra Running Foods: At the Aid Stations

33Shake Endurance Shakes with a Herbal Life Free From Kicker

There are so many natural goodies in a 33Shake Endurance Shake it’d make clean eats brigade blow a fuse in their Nutribullet. Besides the all-natural goodness, the biggest thing they have going for them is that they taste great. You can choose to mix them with milk but I prefer to have them with water and topped up with 26g of Herbal Life Free From meal replacement for an easy-to-digest hit of energy replacement on longer stops. I first used this combination out at the Marathon des Sable in 2015 as a fuss-free breakfast and now I find it’s a fantastic way to get loads of calories in without a big burden on the stomach. I can get moving at pace again far quicker out of an aid station than I might if I had a bowl of pasta.

Pip & Nut Butter Squeeze Packs

It helps to have something savoury in your snack bag to counterbalance all the icky, sticky sweetness you get from most race fuel. I’ve found that the super portable 30g sachets of various flavours of nut butters from the Pip & Nut people can work a treat, provided that is you have plenty of fluids to wash them down with. Make the mistake of eating one of these four miles from water and you’ll regret it. Great for getting a bit hit of calories in at aid stations where you’ll stop for longer. The coconut almond and almond butter ones are particularly good.


If there’s one food I’ve found that helps me out of a stomach-flipping nutritional hole on ultra runs it’s cold watermelon. It’s got a lot going for it.

  1. It melts in the mouth.
  2. It’s full of sugary water
  3. It’s not only refreshes but it also helps rid your mouth of the yucky taste of the other stuff you’ve been forcing down, replacing it with a clean tastes that doesn’t linger.

The only thing I can see that it has going against it is that it’s not that portable. I make my crew cart it around with them and hand it over at aid stations but not quite sure what I’d do on a solo run.

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