While it’s true that one of the side effects of the ketogenic diet is weight loss, anyone who is on keto with a weight loss goal has thought about adding a workout routine into the mix. However, there have been some complaints about the efficacy of keto when it comes to doing serious gym work. In short, will training performance be lacking while you’re on the ketogenic diet?

Just the Facts

In most cases, adding a workout to your day will help you to lose weight. In fact, any workout helps if you were sedentary before you started keto. Did you sit at a desk all day? Walk a mile in the evening after dinner. If you weren’t sedentary before, you may want to either increase the amount of exercise you do or increase the intensity. Adding a few days of HIIT training, or a dance class may be just what you need to help jump-start your weight loss.

However, many people find that they don’t need the gym to lose weight. Weight loss on keto tends to happen without going to the gym. If you’re happy with the rate of your weight loss, then you keep doing you!

Loss of Performance

There’s been a lot of coverage about whether or not the ketogenic diet causes you to lose performance in the gym. To properly answer that question for the average person that wants more information on the keto diet, I need to do a deep dive on a few subjects.

First, it’s important to know that your body uses carbs to fuel your workout. That’s why the people racing in the Tour de France binge on pasta every night of that race, and why Michael Phelps boasted of his 12,000 calorie diet while he was training for the 2008 Olympics. The diet, which included two pounds of pasta per day, would fuel his marathon swim and weight training sessions.

The problem with using carbs as fuel for a workout (and the reason Michael didn’t just eat one carb-loaded meal per day) is because your body can only store so many carbs. Eventually, your carb fuel is going to run out.

As you become fat-adapted, the fat either on your body or that you consume, fuels your workout. You will burn through those twenty grams of carbs that you do consume in a pretty short time frame. After that, you’re burning fat. And because we can store a whole lot more fat than carbs, fat is actually a better fuel for most workouts. You’re less likely to fizzle out three-quarters of the way through your workout (this is also known as bonking) because you don’t have the blood glucose drop that you would have if you were carb-fueled.

So, for most of us, working out while fat-adapted and in ketosis is actually beneficial to the workout. There’s no performance drop.

Ketosis Doesn’t Make You a Better Athlete

While it’s true that unless your body fat index is below about 8% you have a pretty much unlimited store of fat, working out in ketosis will not make you a better athlete. The reason for that has to do with the efficiency of your body. It takes more oxygenation to fuel your body completely from fat. So you have to work a little harder to get to those fat stores. If you ran an eight-minute mile before you started keto, then keto alone will not reduce the time it takes you to run the mile. Weight loss or muscle gain may impact your time, but ketosis alone will not cause gains.

The Other Shoe

You’ve been waiting for it, right? I’ve used a few words in the paragraphs above that may have given you some hint that what I was saying about no performance drop might not be true for everyone.

For some people, like professional athletes who spend hours a day in the gym, weight lifters who are looking to sculpt their body into the type of shape that would make Dwayne ‘The Rock’ Johnson jealous, and people who regularly do sports that involve long play periods, keto may not be the best way to go.

Let me clarify here.

For the average person who does keto for weight loss or to maintain their goal weight, and who hits the gym a few times a week for HIIT sessions or an intensive cardio class, your training performance will not be limited by staying strictly keto. You’ll still be able to do an hour-long aerobics class or a crazy spin routine.

But if your goal is to do intense body sculpting, or if you’re an Olympic-class athlete, carb cycling or doing keto during off-seasons may be a better way of eating for you. This allows you to take advantage of the readily available fuel in carbohydrates during more intense training times, and then to become fat-adapted when you’re slowing down. Keto can still fuel incredible workouts, but carbs may be more appropriate for you during certain stages of your training year.

How to Make the Most of Your Fat-Fueled Workout

I have a few pieces of advice to make your workouts the best they can be.

• Workout fasted if possible. For me, that means I work out first thing in the morning. I take MCT capsules before I leave, and drink my BHB drink while I’m driving to the gym.
• Break your fast after you work out. I break mine with my fatty coffee.
• Vary your workout. Do HIIT some days, and then something with less intensity some days.

For most of us, keto is not going to impact our training at the gym. If you’re an endurance runner or considering an Olympic bid, then you may want to find a different way of eating, at least for during your hardcore training season.

Want more tips about the ketogenic diet and training performance? Join my Facebook group and get to know thousands of other keto’ers who can give you the benefit of their experience!

You got this!

Leta ~ Intentionally Bare

❗ Health information given here is based on public research and is not meant to take the place of your doctor's advice. Always do your own research before trying something new.