Can the Keto Diet Decrease Your Fitness Performance?

Can the Keto Diet Decrease Your Fitness Performance? No.

Dr. Berg refers to studies that demonstrate the increase in performance for athletes. I was unable to find the link to the studies he referred to.

In this video Dr. Mercola interviews Dr. D’Agostino who tells us how the Ketogenic diet increased the performance of navy deep sea divers. Here is the link, Dr. Mercola and Dr. D’Agostino on Ketogenic Diet

When you run your body on ketones, you get less oxidative stress, meaning that your organs and tissues don’t break down as easily.

Two of the top ultra marathon runners are on keto. One of them, Zach Bitter, took the US record for a 100-mile event, done in 11 hours and 40 minutes.

It’s not carbs that build muscle, it’s protein. Strength training also builds muscle. While it’s true that insulin is anabolic, which helps your muscles grow. But two things stimulate insulin; one is carbs, the other is protein. Your muscles are built out of protein not carbohydrates.

Every time you consume protein you’re going to increase insulin, but when you do a keto plan you’re going a low-carb. When you go low carb, and combine it with intermittent fasting, you fix something called insulin resistance. Most of the population has this.

  This means your cells need more and more insulin to offset the effect of eating too many carbs.

When you fix insulin resistance, you increase the absorption of amino acids. You increase the nutrients a lot more.  

You increase insulin more.  Your body uses insulin more effectively. When you do a healthy keto plan, your body runs on ketones, fatty acids, and part of it still uses a little bit of glucose even though you’re not consuming glucose, your body has the ability to make its own glucose in the liver, a process called gluconeogenesis. Your liver can make glucose from protein and fat so we really don’t need carbs as a requirement.

When you start keto, you go through keto adaptation. You may experience fatigue. Increase your B vitamins and minerals. This is a temporary phase, perhaps three to four days. Once you tap into your fat reserves, you will have more energy. Your performance will improve. You’ll have more endurance.

Some athletes become fat burning machines. The truth is, when you eat high carb, you’ll feel more fatigued and your performance will suffer because the higher carbohydrate means more insulin, which means more blood sugar issues which, means more oxidative stress to the body and you never get a chance to tap into the fat because you’re running off your stored glycogen and ketones.    

You’ll have higher insulin along with blood sugar issues and more oxidative stress. The keto diet is more beneficial for athletic performance.

Ketones and Intermittent Fasting have a muscle sparing effect they spare protein. You will stimulate growth hormone you’re not going to lose your muscle mass.

In summary, keto if done healthily can increase your performance not decrease your fitness.

I encourage you to read Drs. Phinney and Volek’s book, The Art and Science of Low Carbohydrate Performance

For better muscle growth consider doing your exercise routine just before breaking your fast. Learn more in Dr. Berg’s video, Exercise – Fasting (it’s a good idea to work out while fasting)

This Post has been condensed from Dr. Berg’s video Can keto diet decrease fitness performance?

Dr. Berg is a chiropractor who specializes in Healthy Ketosis & Intermittent Fasting. He is the author of the best-selling book The Healthy Keto Plan, and is the Director of Dr. Berg Nutritionals. He no longer practices, but focuses on health education through social media. He has taught students nutrition as an adjunct professor at Howard University.

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