How to Exercise on the Keto Diet

What Can I Eat in Keto When Exercising?

Athletes and non-athletes alike will usually eat the same type of keto-approved foods, but depending on your goals and type of exercise, you might need to bump up your caloric intake and/or fat intake.

You see, exercise demands a lot of energy, and the goal of ketosis is not to starve yourself but to feed your body with the fats and moderate amounts of protein it needs to get ahead.

Using a ketogenic calculator can help you estimate your specific macronutrient goals and are easy and free to use; just be sure to set your goals to a higher energy expenditure to reflect your workout goals.

HERE ARE A FEW KETO CALCULATORS TO GET YOU STARTED:

1. https://www.ruled.me/keto-calculator/
2. https://www.perfectketo.com/keto-macro-calculator/
3. https://keto-calculator.ankerl.com/

ATHLETES FOLLOW ONE OF THREE KETO DIET AND EXERCISE PLANS:

• Standard Ketogenic Diet (SKD): 20-50 grams  of net carbs per day, this is what most people follow
• Targeted Ketogenic Diet (TKD): 20-50 grams or less of net carbs taken 30 minutes to 1 hour before keto exercise, best for athletes with high-intensity activities
• Cyclical Ketogenic Diet (CKD): Eating low-carb keto for several days, then eating higher-carb for a couple of days, best for athletes who do marathons, etc.

Many athletes, however, will only follow a targeted or cyclical ketogenic diet on training days and follow a standard ketogenic diet on other days.

This helps the body become fat-adapted and then “cycle” between fat and carbs as needed on more intense days when working out demands fast-acting fuel.

For most beginners, though, simply following a standard keto diet with regular cardio workouts is more than enough to expedite the fat loss effect.

What Types of Athletes Benefit From the Ketogenic Diet?

Athletes that require sustainable energy often report excellent results with the keto diet.

However, being in ketosis could also help if you enjoy running marathons, are a swimmer, enjoy hiking, or biking, plus so much more.

Athletes seeking to shed fat fast may also appreciate the ketogenic diet as a nutritional solution that supports intense workouts like weight-lifting for a quick trim, but it can also be used to maintain muscle mass and body composition to great effect.

In short, almost all athletes can benefit from the ketogenic diet.  

Carbs Vs. Ketones: What’s the Best for Me?  

Ketosis offers athletes a unique opportunity to change how they fuel their body.

Rather than depending on carbs, for a short release of energy, ketogenic athletes use ketone bodies (either taken as a natural supplement or made within the body during a state of ketosis) for a boost of energy.

This is particularly important if you rely on duration or demand constant energy from your workout, which many people do.  

However, in many cases, simply achieving nutritional ketosis (eating 20-50 grams of net carbs per day) is enough to cause fat loss and increase performance once you’re fat-adapted (1).

There’s no need to complicate the diet or add in carbs unless you are a competitive athlete with high energy expenditure.

Merely being in ketosis is itself a great energy boost.

How Keto Exercise Can Improve Athletic Performance

Recently, athletes and exercise scientists are beginning to realize the benefits of a Ketogenic Diet for both stamina and performance.

Researchers from Saint Louis University found that men and women who followed a ketogenic diet performed better when participating in marathons (2).

They were able to run faster and further simply by being in ketosis. This is because athletes who are fat-adapted can call upon an almost unlimited supply of energy in the form of stored body fat.

Allowing the athlete to go harder and longer during their training and competitions.

The Benefits of Keto Exercise

While it’s true that any type of exercise is a great idea, the ketogenic diet offers athletes a unique opportunity to improve their overall health in ways that a carb-based diet cannot; from improved bone density to stamina, more world-stage athletes (like LeBron James and Tim Tebow) are switching to the keto lifestyle.

Not to mention, the reason many people keto exercise is to fight heart disease; which a ketogenic diet fully supports thanks to its anti-inflammation and LDL cholesterol-fighting properties.

KETO DIET AND EXERCISE OFFERS A UNIQUE RANGE OF BENEFITS:

• Improved bone density: Studies show that athletes who participated in resistance training were able to enhance their mineral bone density.
• Improved cardiovascular health: Athletes on a ketogenic diet improved their overall cardiovascular health, with some athletes dropping their LDL cholesterol levels.
• Improved stamina: Ketogenic athletes improved their overall stamina, and were able to perform for longer than when consuming a carb based diet.
• Improved fat burning: Once athletes become fat-adapted, they can expect to burn 2-3 times as much fat per the same intensity of training.
• Improved glucose resistance: In fat-adapted athletes, researchers found that carb restriction improved blood sugar levels and helped athletes use the same amount of energy more efficiently the longer they stayed fat-adapted (something carbs cannot offer).      

Check out our complete ketogenic grocery list to see what food items you can bring into the home to remain in ketosis.

What Types of Exercise Can I Do While In Ketosis?

When you are in ketosis, the following exercises have been proven to be highly effective:

1. Aerobic exercise: cardio exercises can be ketogenic when they are long duration but low impact, meaning you do a little for a long time. This makes them ideal for beginners or people at risk of intense workouts. They also happen to be very prolific for fat loss.
2. Flexibility exercises: exercises such as yoga are helpful for stretching out your muscles, supporting joints, and improving range of motion.
3. Stability exercises: these can help improve your core strength and are a great way to burn fat because, during low-intensity aerobic exercise, the body uses fat as its primary energy source, giving you an advantage.

Anaerobic exercise is recommended on a keto diet: these are the opposite of steady-state cardio and are typically high-intensity sessions for short durations.

While these can be great for experienced athletes, they do typically rely on carbs for a jolt of unsustainable energy.

How Often Should You Exercise on Keto?

Exercise plans are different for everyone. Picking the right combination between a ketogenic diet and exercise routine is what will determine how you lose weight.

There are three types of exercise to consider: athletic, cardio, and weightlifting.

Athletic

While there is some supporting evidence that shows a ketogenic diet can increase endurance, there is not enough to suggest that keto diets are the best option for athletes (2).

Many athletes may notice rapid weight loss during the initial 1-2 weeks of their diet. Then, they’ll experience a less intense, consistent weight loss throughout their training.

Other athletes may notice difficulty in maintaining energy during their workouts as their bodies transition into ketosis. Sports that require small bursts of energy should still be accomplishable, like powerlifting.

Cardio

Cardio exercise is a fabulous method for those on the ketogenic diet. Cardio does not require high intensity, and it focuses on endurance and consistency.

Even if you’re not an athlete, you may find your ability to maintain a cardio workout becomes easier after starting your ketogenic diet. Some forms of cardio are running/jogging, cycling, interval training, swimming, or aerobics.

Weight Lifting

If you want to build muscle mass while on the ketogenic diet, performing weight lifting sets that are less than 10 seconds long will work without exhausting you. 

Increase your weights every week to improve your muscle mass. If you’d prefer to lift lighter weights with increased reps, then you’ll need to increase your daily carbohydrates as well.

How Much Fat Should I Eat When Working Out?

One of the biggest differences in the ketogenic world is that athletes are encouraged to eat high-calorie meals while keeping their body fat in check…

Or sometimes, losing their body fat without sacrificing strength, muscle mass, and performance.

Which, slightly goes against the grain since most people are typically told to reduce their calorie intake while increasing their high-intensity workouts.

The last advice does not support a pleasant experience and can damage your metabolism.

Plus, eating fewer calories on a carb-rich diet will only make your body feel deprived and as if it is starving. In a ketogenic diet, your body turns to its internal fat deposits for fuel and powers on ahead.

Let’s take a look at some simple ways to boost your workout in ketosis.

When is the Optimal Time to Eat With Keto Exercising?

The easiest way to prepare for a keto workout is to make sure your diet is on-point.

Some people choose to eat before a workout, but in many cases, doing cardio in a fasted state and eating within 30 minutes of your workout is a much better system.

Your body calls on nutrients to repair the body after an intense workout and stores food in states of inactivity.

Eating after your workout will help prevent fat-storage, and instead, use that energy to burn off more stored fat while healing your body.

Make your calories work twice as hard by eating after your workout (but do not hurt yourself). If you get hungry during a workout, by all means, stop, and never skip on hydration.

Medium-Chain Fats Pre-Workout

If you’re ready to crush your keto workout, medium-chain fats (or MCTs) are a fantastic way to level up.

Taking MCTs 15-20 minutes before your workout produces an instant shot of energy without causing a spike in blood glucose like sugar-rich, pre-workout supplements.

This means you won’t feel a huge crash in energy during or after your training session.

Another technique you can use before your workout is to take 10 grams of branched chain amino acids with your MCTs. These can give you plenty of energy while kick-starting the recovery process.

Research also shows that eating two tablespoons of MCTs per day is a great way to lose fat naturally and stabilize blood sugar levels. Just make sure to split them up as too much MCT oil can cause gastrointestinal distress.

Use HMB To Protect Your Existing Muscle Mass

Lifting weights and exercising hard can be an intensive process for your body. It’s during this time that you’re actually tearing down the muscle.

Only after you are finished, does your body start the process of rebuilding itself into something bigger and stronger. And one great supplement that could help is HMB.

β-Hydroxy β-Methylbutyrate (HMB), is an anti-catabolic-superhero that can take your workouts to the next level. HMB is the broken down version of leucine (an active metabolite and one of the essential amino acids). HMB slows muscle protein breakdown while speeding up protein synthesis.

Which is also what amino acids are supposed to do. If you’re looking to increase strength, HMB can play a small, yet vital role in increasing muscle mass.

By breaking down your muscle more effectively, your body can heal itself faster and improve your gains.

• If you’re into endurance sports, such as cycling, running, or swimming, HMB can help speed up the improvements in performance gains.
• When it comes to compound lifts – squats, incline bench, deadlifts, etc. – HMB aids in strength training.
• HMB reduces recovery times for most workouts, as well as recovery times for injuries.

Working Out While Fasting

Intermittent Fasting: Should You Exercise on Empty?

As noted above, working out in a fasted state is a great technique for athletes who enjoy cardio and endurance sports.

As these low-impact activities rely on sustainable energy, your body will be forced to call upon fat reserves to fuel itself. 

The only time you need to worry about carbs is if you are a high-intensity athlete, and lift crazy amounts of weight, etc.

For most athletes, simply adding in natural supplements like HMB or MCT, is enough to get the results they want.

Intermittent fasting, which can involve anything from fasting for 14 hours at a time to forgoing food a couple of days a week, is all about restricting food consumption during specified periods of time.

You consume little to no calories during “fasting” periods and normally eat during “feasting” times.

The result is impressive weight loss, according to many devotees of the keto diet.

Some intermittent fasting methods even claim this on-and-off eating plan can help regulate blood sugar, prevent diabetes, lower the risk of heart disease and slow the aging process (3).

Does Fasted Cardio Burn More Fat?

Let’s start this section with the caveat that nothing about the human body has a simple yes or no answer.

Fasted cardio provides many benefits and can burn more fat than a carb-fueled workout. 

But, it really comes down to the types of keto diet and exercises you do and how fat-adapted you are; there may be a transitional period, and you may experience keto flu while adapting to working out without carbs.

Fasting before a cardio workout (commonly, an athlete may stop eating after an early dinner and then work out in the morning before breakfast), is a great way to encourage your body to call upon stubborn fat for fuel.

Where things get complicated is what happens to your body after your workout: what you do in the gym is second to what your body does after the gym.

What you eat and when you break your fast is paramount to success. Eating carbs at this time would trash your results.

Eating clean and healthy fats will help you sustain the fat-blasting effects of ketosis.  

Can I Work Out in a Fasted State?

Can you "Carb-Load" and Stay in Ketosis?

Some lifters, like EAS Myoplex athlete Jason Wittrock, say they can work out and carb load and not be kicked out of ketosis, but this isn’t true of most people.

Carb-loading causes keto problems because, fundamentally, you are offering your body an alternate fuel and will confuse it. In most cases, it is considered ill-advised to consume a high-fat and high-carb diet.

What Happens in a Fasted State

More athletes fast to improve their results. When you are in a fasted state, your body is in a hypervigilant state of ketosis.

To induce fasting, you restrict the times at which you can eat to prolong the times when your body does not have to process and store fat.

The main difference when working out in a fasted state is that you should program your schedule to allow you to eat 30 mins after your workout. 

Your body will demand energy during this time, and it isn’t healthy to avoid eating altogether.

Researchers have also found that athletes who consume protein within 30 minutes of exercising in a fasted state reported increased muscle protein synthesis, boosted thyroid, and also protect themselves against declining testosterone levels (in men).

For example: if you start a fast at 6 pm and workout at 6 am, you will have experienced a 12-hour fast. You can follow this up with breakfast at 6.30 am, after your workout.

Of course, if you feel faint or dizzy, or experience other symptoms, it is important to stop your workout and eat to feel better. Working out in a fasted state is only for experienced athletes. You should start slow and build up.

Keto Pre-Workout Options

For those who want to supplement their workout without increasing carbohydrates, below are a few suggestions of what to consume while maintaining ketosis:

Fat Snacks

Many ketogenic foods are high in fat, and you can drink them pre-workout for energy:

• Avocados
• Low-carb nuts and seeds
• Full-fat smoothies
• High-fat cheese

Chocolate Ketones

Exogenous ketones can be supplemented in the diet to add ketones to your bloodstream directly. This gives you a significant boost of energy before any workout!

Including a scoop of chocolate ketones in your pre-workout is not only delicious, but is simple to add to smoothies, fat bombs, or pre-workout shakes.

Hydration: How to Balance Your Electrolytes

One of the most important factors when working out in ketosis is to hydrate. While we all know that water is essential, this is even truer when on a ketogenic diet.

You see, when you’re in ketosis, your body experiences something called the “whoosh effect.”

When you eat carbohydrates, each gram that gets stored in your body also holds 2-3 grams of water. Just like a dry sponge, carbohydrates suck up water. When you reduce your carbs, in the beginning, you’ll experience a quick drop in water weight plus more frequent trips to the bathroom.

So, when you lose water, it is important to replace those fluids along with the electrolytes in them.

Drinking water is not enough and may cause you to experience the symptoms of keto flu: if you feel lethargic, have a headache, feel constipated, or lacking energy, you might be experiencing an electrolyte imbalance.

The easy way to hydrate and replenish this imbalance is to drink electrolytes, sometimes called ‘smart water,’ to replace the lost salts from sweating.

Drinking regular water is not enough and can drown you in extreme cases, due to reverse osmosis.

Unlike eating, you should not withhold water. 

If you are fasting, you should drink even more water and electrolytes to compensate for the ketogenic diet’s desire to flush out toxins.

What Are Electrolytes?  

If you’ve ever looked at your sweat rag after a brutal workout and saw a white residue, you now know what electrolytes look like. 

Water follows the electrolytes (thanks, osmosis), and as the glands fill up, they release the mix onto your skin.

These salts (calcium, potassium, magnesium) are what give it a bitter taste. 

When there are too few electrolytes, the walls of our cells are unable to hold themselves up and become deflated. 

This can quickly become a life-threatening condition.

Common electrolytes are sodium, magnesium, and potassium. Many people, especially athletes, are deficient in the latter two. You can buy supplements to add to water.

Drink at least one serving per day; more on days you workout.

What are the Best Ketones Supplements for Athletes?  

MCT oil

No locker room talk is complete without MCT oil. Often touted as a holy grail for those in ketosis, MCT oil is a staple for anyone on a keto diet.

“MCTs” are medium-chain triglycerides, a form of saturated fatty acid that has numerous health benefits, ranging from improved cognitive function to better weight management.

What makes MCTs so unique, however, is they are used right away, almost like a carb, but for ketosis. 

MCT is easier to digest, and the body can call upon it for energy very quickly. Making it an ideal companion for workouts.

And, as MCTs have antibacterial properties, they can also help boost your immune system. Taking a tablespoon of MCT oil in your morning coffee is a simple way to fuel yourself.

You can also take another tablespoon before working out. But err on the side of caution, and build up your resistance to eating raw oil slowly. 

This is definitely a case of “too much of a good thing” coming true.

Exogenous Ketones

Do you want all the benefits of ketosis without changing your diet? Scientists as the “fourth macronutrient now tout exogenous ketones,” and you can take exogenous ketones in a shake or a shot.

Currently, when you look on most labels, you won’t find “exogenous ketones.” However, what you will see are the letters BHB, or Beta-Hydroxybutyrate. 

As this supplement activates ketosis, it’s a great option for athletes (especially if you don’t want to carb-load).

Exogenous ketones should be taken in addition to nutritional ketosis for the best results and can expedite the fat-adaption process. 

This is especially helpful for athletes who might be at risk of keto flu when adapting, or who generally call upon larger energy demands.

Simply take a shake or a shot containing lab-certified Beta-Hydroxybutyrate before or after your workout to replenish your electrolytes and meet your energy demand.

Ketone Esters

These are the new kids on the block and are set to change our understanding of macronutrients forever. 

Taking ketone esters means you're getting the raw BHB ketone itself without any salts or other compounds bound to it.

The benefit of esters is that the raw form allows the body to use the ketones more quickly. 

They’re limited in where you can buy from (only one company owns the patents) and very expensive compared to BHBs and MCT oil. 

However, where these really shine is for military or Olympic level pursuits, where nothing less than excellence is desired.

Raspberry Ketones

Finally, this one is a red herring and is not a true ketone - despite the name. 

Raspberry ketones had a moment, and sometimes appear in search results, but they have nothing to do with keto or working out.

They are, at best, an antioxidant, and should generally be avoided due to the many brands now on sale that have not been vetted or certified.

Resources  

1. https://www.ncbi.nlm.nih.gov/pubmed/26892521   
2. https://www.ncbi.nlm.nih.gov/pubmed/19373224  
3. https://www.ncbi.nlm.nih.gov/pubmed/7000826