Top 3 Myths about Exercising on a Keto Diet

Who says you can't build muscle while following the keto diet? Let's break down the three biggest misconceptions about the ketogenic diet.

You can’t work out on a ketogenic (keto) diet, right? Wrong! A keto diet emphasizes eating fat and protein over carbs and usually requires you to restrict your carb intake to less than 50 grams per day, but this diet doesn’t preclude you from working out and building muscle. In this article, we tackle three major myths about exercising on a keto diet.

Myth: You Need Carbs to Build Muscle

There are three main elements to building muscle:

  • Consuming a calorie surplus. To build muscle, you need to take in more calories than you expend, but those calories do not have to be from carbs.
  • Eating protein. You need to consume 1 to 1.2 grams of protein per pound of lean body mass to build muscle mass.
  • Promoting hypertrophy when training. Hypertrophy, which simply means increasing tissue size by increasing cell size, happens with strength training. Doing eight to twelve reps when lifting weights will put your muscles into hypertrophy.

As you can see from the list above, none of these steps require a high carb intake. A keto diet limits carbs so that the body goes into ketosis, a metabolic state that burns fat by converting fat into ketones. Eating fewer carbs means you are restricting your body’s glycogen or glucose storage from carbs. While increased glycogen can help you build muscle, you can get all the glycogen you need from your protein intake. From the three elements above, it is clear that you can build muscle without many carbs on a keto diet.

Myth: Your Performance Will Suffer

While it is common for people to feel fatigued during the first week or two of a keto diet, their energy levels bounce back and often increase as the body becomes used to burning fat. Some people worry that this transition from burning glycogen to ketones will hurt their performance, but this is not the case. A 2012 study testing the physical performance of gymnasts on a ketogenic diet found that the diet decreased weight and body fat without decreasing the performance of the women.

If you have recently become interested in high-intensity activities, there is a modified keto diet called the Targeted Ketogenic Diet that allows you to eat carbs before your workouts to give you a boost of energy. Eating carbs 30 to 60 minutes before a workout will take you temporarily out of ketosis but doing so will not throw off your entire diet. Another option that is helpful for bodybuilders and high-intensity athletes is the Cyclical Ketogenic Diet. This diet includes five to six days of a standard keto diet accompanied by one to two days of high-carb intake.

Myth: You Will Lose Muscle Mass

The relationship between gaining muscle and losing fat is a complicated one, but there is no evidence to support the idea that you will lose muscle mass on a keto diet. In fact, a 2017 study of college-aged men found that a keto diet coupled with strength-training helped the men build muscle and increase strength. There is evidence that ketones, adrenergic stimulation, and protein intake contribute to sparing muscle mass on a keto diet.

As you can see, it is entirely possible to work out on a keto diet, and Lifesum’s keto diet app provides an easy way to track your macronutrients.

All of the content and media on Lifesum is created and published for information purposes only. It is not intended to be used as a substitute for medical advice or treatment. Users should always consult with a doctor or other health care professional for medical advice.

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