Building Muscle on Keto Diet: Full Guide Here

Can you build lean muscles while starving yourself of carbohydrates? It sounds implausible building muscle on keto alone, but it is actually possible. You may know the keto diet for its exclusive benefits on weight loss, but it is also quickly becoming bodybuilders’ most favorite meal plan.

Keto diet can be used to speed up a fat loss without negatively impacting strength performance. When balanced protein intake is added into the equation, the result is more muscle mass.

Man Back and Bicep

What is a Ketogenic Diet?

A ketogenic diet (KD) is a meal plan that comprises of high-fat, sufficient proteins, and low levels of carbohydrates for metabolic needs.  This diet essentially forces your body to use fat as the primary fuel source. A standard ketogenic diet consists of 80 % fat, 15 % proteins, and 5 % carbs.

Back in the golden days of Bodybuilding; Arnold Schwarzenegger, Frank Zane, Lu Ferrigno, Ric Drasin, and Franco Columbu era. These guys hardly consumed any carbs, they did not follow the standard keto diet as their protein intake was higher. Arnold often talks about consuming 250 grams of protein a day.

Ric Drasin has also mentioned a lot of these guys would consume a lot of carb-heavy food on a Sunday.

As you can see these guys did not follow a standard keto diet but they did build amazing bodies on a very low carb diet.

If you are interested in Keto, then I highly recommend the 28-day Keto Challenge or the 3-week ketogenic diet, both of these books are excellent keto resources.

For a more in-depth look at the keto diet, I’ve written an article on the ketogenic diet – the ultimate beginner’s guide to keto.

The Role of Carbs in Bodybuilding

Carbohydrates are needed for glucose, the primary fuel source in a non-keto diet. Carbs cause the secretion of insulin; the latter is a growth hormone that supplies the body with energy, helping muscle cells to grow. Eating carbs around your workouts can accelerate Muscle Protein Synthesis (MPS), but studies show that keto diets work even better.

Cutting Down on Carbs

High amounts of carbs can cause stagnation in muscle building. Researchers have found that a low carb diet consisting of 20-50 grams of carbohydrates is actually the fastest way to build lean muscles. In a study published in NIH, a few bodybuilders were given whey (proteins) and others Maltodextrin (proteins plus carbs) after a series of workouts. Results showed that carbs as an after workout meal doesn’t accelerate muscle protein synthesis.

Muscle protein synthesis requires the special protein mTOR, which functions as the pathway for the manufacture of muscle proteins. However, the process also involves resistance training to boost muscle volume. Without consistent weight lifting, for instance, the rate of protein breakdown would be highest than the speed of protein synthesis and protein breakdown, leading to muscle loss.

Wild Rice

You then realize that to build lean muscle on a keto diet, exercise is a critical requirement. On the flip side, instead of ravaging lots of carbs after a workout, you will need to replace that with proteins. Amino acids are required to stimulate mTOR and the expansion of muscle tissue.

Post-workout protein intake can help optimize MPS (muscle protein synthesis). Animal proteins are preferable when it comes to building muscles on keto. Unlike plant proteins, they have the right amounts of leucine needed for MPS. Also, you could take BCAA (Branched Chain Amino Acids)

You would also have to consume sufficient amounts of proteins with every meal to help maintain your new muscle mass. The MPS process should continually be higher than MPB (muscle protein breakdown) even at rest.

What Happens During a Keto Diet?

On a keto diet, glucose levels drop, and reserves become depleted. The same happens with intermittent fasting. The remaining glucose levels become unable to sustain fat oxidation and then supply energy to the brain. Therefore your body is forced to find an alternative source of energy. The new energy is supplied by ketone bodies, generated via the ketogenesis process in the liver.

In the initial stages of ketogenesis, your brain’s metabolism would require about 10g of glucose 16% of this glucose comes from glycerol, but a majority is gleaned from protein via gluconeogenesis.

This process is energy-intensive, but as you progress with a ketogenic diet, fat gradually replaces protein as the source of glucose. The subsequent proteins consumed in a keto diet would be tasked with maintaining your body mass.

If the variables in a keto diet for muscle building are kept constant (resistance training, high fat consumption, and enough protein), the meal plan can lead to a faster weight loss and increase in lean body mass.

This study carried out in 2002 shows that on a low carb diet, your body is burning fat at an expedited rate, which leads to an increase in lean muscle mass. Just remember that as that happens, you would need adequate calorie consumption (through fat and proteins) to maintain your body mass.

Working Out on a Keto Diet

Building muscles on keto is easier than you think. A ketogenic diet has a positive effect on performance. After becoming keto adaptive, the lethargy and general weakness experienced in the fast few days of a keto diet disappear.

In the first phase of ketosis, try lowering your rep ranges to 3-5 reps and increasing your rest periods. That’s because, at that stage, your body is gradually shifting from proteins to fat as the source of energy.

building Muscle on Keto

As your body becomes efficient at using fat for energy, you can get back your stamina in the gym just as before. You can also take supplements to help boost performance when working out on a keto diet. They might help to counteract strength loss and muscle atrophy.

A calorie-sufficient ketogenic diet with an ample amount of protein would be highly essential. Keto is not a crash diet and, therefore, cannot result in metabolic imbalances that slow down performance. Remember that when lifting weights with a goal for more muscle, protein is the Holy Grail you need.

Studies show that on a keto diet, bodybuilders would need at least 1.4 grams of protein per pound of body weight every day while maintaining a low carb intake. This amount of protein can help to prevent muscle loss even on intermittent fasting. Some ideal protein sources for bodybuilders on a high-fat diet include fish, meat, eggs, and high-fat dairy.

Benefits of Ketosis on Athletic Performance

Reduced inflammation: Resistance training involves prolonged and heavy exercises that can cause an inflammatory response or oxidative stress. The latter is a shift in the balance of free radicals in the body that may cause tissue damage. Research shows that by eliminating sugars, a keto diet can help to reduce inflammation.

Reduced fatigue: In the long term (3 weeks to 30 days), a ketogenic diet can improve your resistance capacity. Apart from having a positive effect on oxidative stress, the diet can help to counter fatigue. As a result, you could push yourself further at the gym without feeling the pain.

Reduced digestive stress: Keto diet helps to calm the symptoms of irritable bowel syndrome.  Digestive stress is often an impediment to bodybuilders epically during cardio and prolonged strength training.

Tips for Working Out on a Keto Diet

Eat fat right before exercising to supply your muscles with the needed fuel. Apart from fats, your low carb diet components should be from non-starchy veggies like kales, and broccoli to boost your antioxidants as well.

Train hard: You need to get enough workout to achieve muscle growth. However, avoid exercises that require short bursts of energy.

Eat enough protein. You must supply your muscles the building blocks they need for growth and your body the energy it needs to function. Proteins can also help to maintain your body mass by compensating for the ketogenic fat loss.

Drink plenty of water:  A ketogenic diet combined with exercise can cause significant water loss.  You will need to replenish your fluids to maintain your performance and achieve a faster recovery.

Maintain your exercise routine: When building muscles on keto, it can be hard to adjust to a new routine. In that regard, don’t implement many new exercises all at once.

Weight Control

On a keto diet, you can lose weight through fat oxidation and general appetite suppression. Weight control plays a big role in performance during bodybuilding. The other methods that people use to improve power-to-weight ratios such as saunas and diuretics can be detrimental to your general health and performance as well.

A ketogenic diet can help to control weight without the loss of lean body mass or performance impairment. The result would be a faster increase in muscle mass.

Weight Control

How to control your weight on a keto diet:

  • Stick to unprocessed and whole foods.
  • Balance your level of physical activity with your daily calories, to build muscles you will need to consume more calories.
  • Try to consume 500 calories extra per day than your body is using. Use our calorie calculator to help you work out your calorie requirements.
  • Minimize excessive ketogenic snack consumption, including cheese, fat bombs, and nut butter. You don’t want to consume more calories than you require.
  • Get enough sleep to tune down your stress levels, this will also help with physical performance.
  • Measure your level of ketosis using keto sticks (the strips detect the number of ketones in urine), and adjust your fat intake accordingly.

I’ve got a free calorie calculator to help you calculate you’re daily calorie requirements.

Strength and Power Output

Remember that insufficient protein intake in a keto diet might reduce your physical performance. Protein is needed to maintain your body mass and supply the amino acids required in MPS. There is also a deficit caused by gluconeogenesis in the first stages of ketosis that needs to be filled by high protein consumption.

On the other hand, maintaining a high fat intake would spare your muscles from a recurrence of gluconeogenesis. In a keto adaptive stage, high fat consumption can help to increase your power output.

How to Maintain Your Strength on a Keto Diet:

Slightly increase your sodium intake: A ketogenic diet can shift your electrolytes and fluid balance, causing you to lose more water. Also, your body would be flushing out excess ketones through urine, causing deficits in sodium and water. Consider increasing your uptake of the electrolyte to help in water retention. Bone broth and chicken soup are good sources of sodium.

building muscle on keto

Drink more water:  If you are building muscles in keto, you will need to drink not less than three liters of water every day while on a keto diet.

Increase your fat intake: As mentioned earlier, when on the keto diet, your body needs to burn fat for its energy needs. Healthy fat choices you can consider include ghee, olive oil, and fish oil.

Take creatine supplements: Creatine can boost performance and muscle strength for bodybuilders on a ketogenic diet. It helps to synthesize and increase the levels of glycogen in your muscle tissues. Glycogen is the stored form of glucose needed for energy production.


Because of the anti-inflammatory and anti-oxidative abilities of a ketogenic diet, as seen earlier, your muscles’ health may improve. Gradually they will toughen up against fatigue and damage, giving you a chance to exercise even harder for more muscle gain.

A study done on keto-adapted ultra-endurance runners shows that in a keto adaptive stage, one can have a high peak fat oxidation.  A 2016 article published in Cell Metabolism revealed that cyclists on a keto diet were able to go further, cycling for longer.

In recent studies, athletes on a keto diet displayed a higher endurance capacity and performance enhancement. This research found that a 12-week keto diet together with a daily treadmill exercise resulted in increased gene expression in markers of fatty acid oxidation. These results show that, indeed, Keto adaptation can be the gateway to higher endurance in physical activity.

How a keto diet improves endurance:

  • Improving the power-weight ratio
  • Increasing mitochondrial muscle volume
  • Boosting oxygen uptake
  • Increasing fat oxidation

Fatigue Prevention and Recovery

When building muscles the leading causes of fatigue include lactate accumulation, oxidative stress, and glycogen depletion. A study on off-road cyclists showed that a 30 Day KD enhanced the lactate threshold of the subjects. It was found that a KD diet helped to reduce lactate build up by 50% half an hour after exercise commencement, as compared to the control group.

Similarly, recent studies show that ketogenic dieting leads to lower lactate accumulation post-endurance training.  These studies show that a keto diet can help to overcome fatigue so that you can work twice as hard for bigger muscles.

Another way a keto diet prevents premature fatigue is through muscle glycogen regulation. On a keto diet, you can maintain metabolic flexibility and conserve glycogen, thus minimizing fatigue.

One Arm Push-ups

Strength Training on a Keto Diet, how to Preserve Your Energy

Avoid HIIT (high-intensity training): Ketogenic dieters that wish to gain muscle mass should stick to strength training. HIIT requires high bursts of power in a short time and should be therefore be left for carb dieters. To find out more about HIIT you can read our article HITT vs Tabatha.

Listen to your body: Don’t lift heavy weights for long when your body is telling you to stop.  Either cut down the loads or take many rests during your workout. Stress and fatigue signs for keto bodybuilders include dizziness and extreme muscle pain.

Cyclical ketosis: To keep up with the energy demands of your bodybuilding routines, consider adopting the cyclical ketogenic diet where you eat a high amount of carbs just once or twice a week. The high carbs will increase your human growth hormone (insulin) for better performance on standard keto days.

As mentioned before this is what the bodybuilders of the golden era of bodybuilding used to do. Normally they would eat a lot of carbs on a Sunday.

Switching to a ketogenic lifestyle doesn’t have to put an end to your bodybuilding ambitions. In fact, it can help you hit your targets much faster, as seen above. A keto lifestyle also improves your health in several immeasurable ways.

My Experience

Before my operation on my foot, I had reduced my carbs. The first week for me was tough as I used to eat a lot of carbs.

I did notice my energy levels had dropped in the gym, but this drop did not last for long. Also, I was able to drop the inches on my waist whilst maintaining my muscles.

Once my body had gotten used to it consuming all those carbs I started to sleep better, my nose was not permanently blocked and stuffy, I also had more energy. Plus, I was looking better.

Unfortunately, being laid up after my operation has set me back a bit, but I’m raring to go again. If you are interested in Keto then I highly recommend the 28-day Keto Challenge or the 3-week ketogenic diet both of these books are excellent Keto resources.

References Used in This Article

  1. Carbohydrate does not augment exercise-induced protein accretion versus protein alone.
  2. Body composition and hormonal responses to a carbohydrate-restricted diet.
  3. Nutritional Ketosis Alters Fuel Preference and Thereby Endurance Performance in Athletes.

Leave a Comment

Your email address will not be published. Required fields are marked *

Share via
Copy link
Powered by Social Snap