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running in ketosis

Running in ketosis

Chubby runners may be convinced that carbohydrates are needed to fuel their long-distance running. You’ve heard the term “carbo-load,” referring to the meal, the night before a marathon. Are carbs needed? Can a high-fat, low carb diet work? And, can you get the fuel you need when running in ketosis? 

What is ketosis?

The ketogenic or keto diet is blowing up the internet right now. You may have heard claims that fat burning, ketosis, helps runners run more efficiently. So, what is ketosis?

Fat as fuel

Here’s what WebMD has to say:

Ketosis is a process that happens when your body doesn’t have enough carbohydrates to burn for energy. Instead, it burns fat and makes things called ketones, which it can use for fuel.

Ketosis is a word you’ll probably see when you’re looking for information on diabetes or weight loss.” 

When training for long races like a marathon, proper fuel is a huge part of your success.  Whether you are consuming carbs or fat, your body finds a way to convert those into energy so you have the fuel to endure for the race.

For more information on the keto diet, check out The Complete Keto Diet Guide.

Carbohydrates as fuel

Carbohydrates are the body’s go-to fuel source. Carbs are quickly and easily converted into glycogen and then stored in your cells. So, when your body needs energy, it can quickly tap into that glycogen storage and release it into your bloodstream for fuel. Ketosis happens when there is no glycogen to be used for energy needs, and it begins burning fat instead.

Running in ketosis benefits

There are many benefits of running while in ketosis. Some runners have reported that while running in ketosis they:

  • No high energy spikes
  • No energy crashes 
  • Don’t have to use high carb gels, bars, or drinks

Fat burning while running in ketosis 

Fat is a smooth burning fuel. It doesn’t spike insulin levels like carbs do. Also, even a very lean and not chubby runner has about 30,000 calories of fat stored vs. the 2,000 calories of carbohydrate stored in the body. You can see why fat is a desirable fuel source.

Carb fuel vs. running in ketosis

The body can more easily convert carbs into fuel. This is true because that is what the body knows how to do. Because of our way of life, our bodies are not accustomed to converting fat to fuel. We have been taught that we need to eat a low-fat diet, rich in grains and fruits, and vegetables. Continuing to eat this way, keeps the body from ever transitioning to burn fat as its primary fuel source.

How to start running in ketosis

Just like anything else, running in ketosis can come with practice and training your body. Runners who know how to get in ketosis will find that while on long runs they can become more efficient at burning fat. Once runners have become well-adapted, they may not feel any difference between burning fat vs. carbs for fuel. Once in ketosis, you may notice that you no longer need to replenish the sugar stores while on a long run.

Diet and lifestyle change

Learning to live in ketosis is an extreme diet and lifestyle change. It requires cutting out most carbohydrates and consuming fats and protein. There are a couple of guys that I follow for ketogenic diet information, Thomas DeLauer and Drew Manning, the Fit2Fat2Fit guy. 

Here are the basics of a ketogenic diet:

  • 70-80% Fats
  • 20-25% Proteins
  • 5-10% Carbohydrates

Fats for running in ketosis

What kinds of fats should you be consuming to get into and run in ketosis? There are a number of health and fitness people that have their own keto programs, but here’s a simplified list of fats to consume:

Healthy fats
  • Olives and Extra-Virgin Olive Oil
  • Coconuts and Coconut Oil
  • Avocado and Avocado Oil
  • Grass-Fed Butter
  • Nuts (Macadamia Nuts, Pecans, Walnuts, Cashews)
  • Whole Creams and Cheese
  • Fish (Salmon, Tuna, Anchovies)
  • Whole Eggs 
Non-Healthy Fats
  • Vegetable Oil
  • Canola Oil
  • Artificial Trans Fats
  • Processed Meats
  • Fried Foods

Proteins for running in ketosis

What kinds of proteins should you be consuming to get into and run in ketosis? 

Here’s a quick list of proteins to consume:

Proteins
  • Chicken Breast
  • Grass-Fed Beef
  • Fish
  • Eggs
  • Turkey
  • Pork

Carbs for running in ketosis

What kinds of carbohydrates can you eat to get into and run in ketosis?

I’ve compiled a simple list of carbs that are ok to consume:

Carbohydrates
  • Broccoli
  • Cauliflower
  • Brussel Sprouts
  • Cucumber
  • Spinach 
  • Kale
  • Asparagus
  • Blackberries
  • Blueberries
  • Raspberries

The lessons learned from ketosis can be applied in a more moderate manner through a method called ‘fat adaptation.’ We’ll discuss that in more detail in another post, but if you’re a runner, you may have already heard about it. If that’s the case, you’re definitely ahead of the curve. 

Have you ever run on an empty stomach and decided to do a longer run than planned? If you have, then your body had no other choice but to use fat for fuel. That was running in ketosis and you didn’t even realize it.

Fun fact about running in ketosis

One pound of body fat equals 3,500 calories. That means a 150-pound person could run for 3 hours and burn a ½ pound of stored fat.

Final thoughts about running in ketosis

There are a lot of different diets out there. The ketogenic diet is really popular right now. But it may have some great benefits for runners. The ability to change your body, to burn fat for fuel, is more efficient and may have even greater health benefits. In later posts, you’ll learn more about the ketogenic diet so you can give it a try and see how it works for you.

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