Endurance Eats: How To Fuel A Long Spartan Event

By: Ben Greenfield

Whether you’re racing a standard Hurricane Heat, a 12-Hour Hurricane Heat or the new Spartan Agoge as part of a Spartan DELTA, it’s crucial that you understand that your body can only store about ninety minutes of the type of fuel—carbohydrates—that is used for high intensity bursts such as burpees and sandbag carries. Once you get past the ninety-minute mark, your muscle and liver stores of carbohydrate (glycogen stores) can become depleted, and your body subsequently turns to fat for fuel.

Now, as I explain in a recent article I wrote on diet, ketosis and fat intake, both the rate at which you exhaust your glycogen stores and the efficiency of your body’s switch from carbs to fat depend on several factors: your diet (e.g., high fat vs. low fat), your training (e.g., doing all your workouts fed vs. including some fasted workouts) and even your genetics (e.g., whether you are a “carb burner” or a “fat burner” by nature). Ultimately, it’s important to understand that, to maintain any semblance of brain and body performance for any event that lasts longer than ninety minutes, you must introduce a slow, steady flow of fuel into your body. This will have a “glycogen sparing” effect, keep you from catabolizing excess muscle, and ensure you don’t get that foggy-brain, sluggish-muscle bonk that is all-too-common as you go ninety minutes and beyond without enough fuel.

The question is: what should you eat to achieve this steady fuel flow?

In the recent Spartan Up! podcast with Sami Inkinen, who rowed from the California Coast to Hawaii while eating no sugar, no grains and no “frankenfuel”-filled sports nutrition products, you can learn how slow-burning fat sources can fuel these long endurance sessions. Sure, for very high intensity workouts, high amounts of fat from whole food sources may leave the stomach too slowly to be of much use, and you may indeed need some carbohydrates in these type of situations; however, during long endurance events, fats fit the bill perfectly.

Here are five proven and beneficial fat sources I recommend you keep in a Ziplock bag, a fuel belt, a backpack or wherever else you find handy:

1. Macadamia Nuts. Chock full of slow-burning saturated fats, macadamia nuts are a tasty, crunchy treat when the going gets hard. Resist the intense urge to get the ones coated in chocolate, which completely defeats the purpose of not dumping unnecessary sugar into your body. Instead, just get them salted and roasted.

2. Pumpkin Seeds. These easy-to-munch seeds are full of iron, which comes in quite handy for endurance events. Don’t get the nasty ones from the gas station that have been coated in canola oil and additives. Instead, grab a pumpkin and roast your own. You’ll have plenty of pumpkin flesh left over that you can add to smoothies. Or, you could simply add a bit of nut butter and sea salt for a tasty snack. Call them “pepitas” if you’d like to sound fancy and educated.

3. Coconut Butter. Coconut butter is also known as coconut manna. It’s a tasty blend of coconut flesh and coconut oil. It’s relatively hard at room temperature and colder conditions, but it can be broken into chunks that are easily transportable and incredibly tasty. This form of fat is also high in medium-chain triglycerides, which actually bypass most of the complex digestive processes and get burnt readily as a fat-based fuel.

4. Chia Seed Slurry. Chia seeds have plenty of fatty acids and amino acids in them, and they can also be soothing to the stomach; however, you need to “activate” them with water (just like a chia pet). One heaping tablespoon of chia seeds will give you about fifty calories of fuel, so, for a long event, you can put several tablespoons into a giant water bottle, shake it up, let it sit for two to twelve hours, and you’ll have a tasty slurry to which you can add stevia, sea salt, lemon or any other flavorings you choose. Then, you can dump this mix into flasks or water bottles. It mixes just fine with any of the other energy sources in this article.

5. Fat-Based Energy Gels. Yes, yes, I know I promised no “frankenfuels,” but the fact is, some nutrition companies do make energy gels that use bases such as coconut oil, chia, nut butter and other non-sugary alternatives with low amounts of nasty additives. There are at least twelve such gels you can stick in your pocket and eat on the go. (Warning: most of these gels should be “chased” with six to eight ounces of water for good digestion).

That’s it. Forego the sugary drinks, forego the “Spartan-esque” fasted approach, and try some of these foods if you’re going for longer than ninety minutes. Do you have questions? Head over to my Facebook page, leave them there, and I’d be happy to help.


This year, Ben Greenfield is completing the Spartan DELTA. Ben is an ex-bodybuilder, Ironman triathlete, Spartan racer, coach, speaker and author of the New York Times Bestseller Beyond Training: Mastering Endurance, Health and Life. In 2008, Ben was voted NSCA’s Personal Trainer of the year and in 2013 and 2014 was named one of the top 100 Most Influential People In Health And Fitness (Greatist). Ben blogs and podcasts at http://www.BenGreenfieldFitness.com, and he resides in Spokane, WA with his wife and twin boys.