The idea of building and maintaining muscles without carbs may sound impossible for some people. It is true that carbs help build muscle, but did you know that ketogenic diet can also help you do the same with numerous other health benefits?
Not only that, some studies have found that the keto diet is more effective in building muscle mass, burning fat, and preventing muscle breakdown than the traditional western diet.
On the ketogenic diet, you’ll also be able to build muscles without the adverse effects of a high carb diet such as fatigue, digestive problems, and cravings. You will also enjoy the mental clarity and improved cognitive function that will help you focus properly during your workout sessions.
We’re going to break the popular myths surrounding the ketogenic diet with evidence. You’ll also see some examples of exercises you can practice for muscle building on a keto diet as well as some easy meals to try.
Muscles are an organ made out of soft fibrous tissues found in the human body and most animals. The primary purpose of muscles is to contract and promote movement or to maintain certain positions of the body. Research states that approximately 40% of your total body weight consists of skeletal muscles and 50-75% of all body proteins . Muscles grow when the rate of muscle protein synthesis is higher than the muscle protein breakdown.
The power output of muscles can be compared to mechanical engines. For instance, a racing car engine and an aircraft engine are only ten-fortyfold more potent than a muscle regarding weight differences.
There are two main types of muscles in the human body (excluding the heart muscle):
1. Skeletal muscle
Skeletal muscles connect the bones in the arms, legs, and spine. They contract quickly to produce rapid movements like walking or holding the body in a particular position. Skeletal muscles are also responsible for immobile actions like clenching of fists. In this case, the muscles contract and work to oppose each other to cancel out any movements.
2. Smooth muscle
These are found surrounding internal organs such as the intestines. Two main functions of the smooth muscles are to move food along the gastrointestinal tract and control the diameter of blood vessels.
General structure of skeletal and smooth muscle:
Skeletal muscle cells are said to be cylindrical, roughly 1-40 mm in length, 10 – 50 μm in width, and have multiple nuclei. Smooth muscle cells are made out of long spindle-shaped cells, and each cell has one nucleus .
Actin is a major protein found in abundance in most eukaryotic cells like the muscle cells. It’s involved in more protein-protein interactions than other protein. Actin is critical for many cellular functions including muscle contraction .
Myosin is a motor protein involved in many cellular movements, including muscle cell movements . The interaction between actin and myosin are crucial for muscle contraction.
Myofibrils are muscle protein strands of sarcomeres, and sarcomeres are long fibrous protein filaments that slide past each other during muscle contraction. A single muscle fiber from the bicep muscles, for instance, may contain 100, 000 sarcomeres and it is sarcomeres that give skeletal and cardiac muscles their striated appearance. In a nutshell: myofibrils hold the muscle cells together and increase in size when your muscle grows.
Activation of satellite cells
The formation of muscle tissues is called myogenesis. Muscle satellite cells are responsible for the growth and repair of muscles. They usually remain low or inactive and come for rescue after an injury or muscle stress induced by exercise . Muscle repair by satellite cells often results in increased muscle size which is known as hypertrophy.
For example, if you practice an intense exercise program such as resistance training, you’ll be causing trauma to the muscle fibers which the satellite cells will consider as muscle injury or damage. The ordinarily quiescent satellite cells will then get activated to repair the muscle fiber by fusing together and to the muscle fibers. New muscle protein strands (myofibrils) are formed when the majority of the satellite cells multiply and fuse to the muscle fibers. This would often increase muscle mass . They would also repair damaged muscle fibers.
After fusing with muscle fibers, some satellite cells also provide new nuclei to promote the growth of muscle fiber. This helps the muscle fibers to synthesize more proteins and myofilaments (actin & myosin discussed earlier) in muscle cells.
Muscle protein synthesis
Protein synthesis refers to the process by which individual body cells build their required proteins. Proteins are the building blocks of body tissues, including the muscle tissues. It is during protein synthesis that the two major muscle proteins (Actin and Myosin as discussed earlier) are created. Protein synthesis occurs at a rapid rate during adolescence and into young adulthood and starts slowing down after the age of 20.
Generally, anything that affects the satellite cells is considered a muscle growth factor.
Hepatocyte Growth Factor (HGF): known as the critical regulator of satellite cells, HGF has been found to be involved in the migration of satellite cells to the damaged muscle area for repairment.
Fibroblast Growth Factor (FGF): involved in muscle repair after exercise, FGF may have a role in forming new blood capillaries during muscle regeneration.
Insulin Growth Factor (IGF): has a crucial role in protein synthesis, regulating muscle mass growth, and muscle repair.
This is the loss of muscle mass and strength caused by old age. The regenerative properties of skeletal muscle have been found to decrease with time, and it’s correlated with the decline in satellite cells activity . That said, the adverse effects of aging have been shown to be improved or even reversed with proper resistance training exercises.
Although men and women respond similarly to resistance training exercises, women cannot grow muscle as quickly as men and one of the key reasons for that is testosterone. As a steroid hormone, testosterone stimulates the growth hormones discussed above and promote protein synthesis in skeletal muscle. Body size and body composition may also play a part in this.
Nutrition and physical activity are two of the significant factors in muscle growth and maintenance. Protein obtained from food sources can be incorporated into skeletal muscle proteins. That doesn’t mean all the excess protein you eat will also convert into muscles, and we’ll be discussing this in detail in a bit.
As stated earlier, resistance training can cause trauma in the muscle cells which in turn activates the satellite cells. The satellite cells will repair and promote new muscle mass growth.
A 2018 study conducted on 24 healthy men found that keto diet can be a better alternative approach to losing fat mass and visceral adipose tissue (belly fat) without losing muscle mass . In this study, the participants were randomly divided into three groups: keto diet group (KD), non-keto diet group (NKD), and a control group. The diets were combined with an 8-week resistance training program.
The results showed that the participants in the keto diet group had a significant reduction in fat mass and visceral adipose tissue. They also did not put on any additional weight or lose muscle mass. No fat mass changes were observed in the non-keto and control groups. However, the non-keto diet group showed an overall increase in body weight.
A lot of people believe that eating more protein means more muscle growth, however, that is not the case. For example, in one study, six healthy young men underwent resistant training followed by consumption of protein drinks containing 0, 5, 10, 20, or 40 g of whole egg protein on five separate occasions. The results revealed that muscle protein synthesis (MPS) remained maximally stimulated at 20 g and they concluded that 20 g of protein is more than enough to promote MPS and albumin protein synthesis after resistance training .
Other studies also show that increasing the intake of protein through supplements, shakes, and intravenous infusion of amino acids can immediately increase muscle protein synthesis but declines quickly and has a short-term effect despite the continued availability of amino acids.
A 2009 study conducted on epileptic children found that branched-chain amino acids (BCAAs) can boost the effectiveness of the ketogenic diet . BCAAs are three major amino acids: Leucine, Valine, and Isoleucine that cannot be adequately produced by the body and would have to be taken orally from dietary foods and supplements.
All the essential amino acids (EEAs) and non-essential amino acids (NEEAs) have to be present in adequate amounts for new muscle protein synthesis to occur. The BCAAs (leucine, valine, and isoleucine) are not only crucial for the growth of new muscle protein, but they also play an essential role as a regulator of intracellular signaling pathways involved in protein synthesis . BCAAs also play a vital role in reducing exercise-related muscle damage and increase the anabolic (growth) rate of muscles while decreasing the catabolic (breakdown) rate [11, 12].
Since the ketogenic diet consists of moderate intake of protein, you can still reap the benefits of BCAA supplements without interrupting ketosis.
The mammalian target of rapamycin (mTOR) is a protein kinase in charge of regulating different cellular functions. A 2017 study conducted on exogenous ketones found that ketones can activate mTORC1 without muscle glycogen resynthesis. They concluded that ketone bodies could activate mTORC1 and protein synthesis in leucine (BCAA) stimulated myotubes .
As stated in the beginning, most people have been trained with the idea that you need carbs to build muscles. Hence they often have doubts about whether or not a keto diet can help build muscles. Some people also get anxious about losing muscle mass while on the ketogenic diet.
We’re here to tell you that you no longer have to believe those myths. We’ve already pointed out some evidence to this in the previous section but here are some more to encourage you.
A 2014 study conducted on college-aged resistance trained men found out that very low carb ketogenic diet not only increased muscle mass, but it increased it more than the traditional diet group . In this study, the participants were divided into two groups: one group for the very low (5%) carb, high in fat (75%), and moderate protein (20%) ketogenic diet, while the other group had a traditional western diet consisting of 55% carbs, 25% fat, and 20% protein. They also participated in a periodized resistance weight training program three times per week. The study was carried out for 11 weeks, and results were measured at week 0 and week 11.
The results revealed that there was a significant increase in lean body mass and muscle mass in the keto diet group compared to the traditional high carb group. Not only that, but there was also a significant reduction in fat mass in the keto group compared to the high carb group.
Another benefit of the keto diet for muscle building is that ketone bodies can prevent muscle protein breakdown . Remember we discussed BCAAs (branched chain amino acids) earlier and how they help with muscle growth and repair? Well, a 1988 study found out that Leucine (a major BCAA) oxidation decreased after the infusion of beta-hydroxybutyrate (a primary ketone body) by 18-41%.
They also found that beta-hydroxybutyrate ketone also increased the use of leucine for skeletal muscle protein synthesis . This means that on the ketogenic diet, ketones can slow down the use of BCAA and preserve it for muscle growth and maintenance.
You still need your required amount of protein per day to build muscle on a ketogenic diet effectively.
If you do high endurance exercise or participate in sports that require a little carb boost, you can eat some carbs and take exogenous ketones afterward to remain in ketosis.
As discussed multiple times throughout this article, resistance training is one of the proven methods to build muscle on a keto diet. So go for it without worrying about carbs because the keto diet has been shown to be more useful for losing body fat and building muscles than a traditional high carb diet.
Eat an adequate amount of fat to maintain and reap the benefits of ketosis as well as building muscles. Eat more fat if and when you feel lethargic.
The ketogenic diet is diuretic which means that you’ll be losing a lot of electrolytes in urine. This increases further during intensive workouts, and losing electrolytes can cause side effects such as fatigue, brain fog, diarrhea, vomiting, muscle cramps, confusion, irritability, memory problems, anxiety, and more.
Those side effects, especially muscle cramps, are the last things you’d want when you’re working out and trying to build some muscle. Get into the habit of sipping some sea salt or Himalayan salt water throughout the day, munch some pickles, eat your avocados, take magnesium supplements, and drink coconut water if you can.
If you recall the studies from the previous section, you’ll see that on a high fat ketogenic diet, increasing the protein to 40 g after resistance exercise didn’t make any difference and the maximal effective state was achieved at 20 g of protein. On top of that, excess protein can stimulate gluconeogenesis, and that may interfere with ketosis.
Dehydration is bad for overall health, and a 2015 study found that dehydration caused significant cellular and whole body stress in athletes .
Push ups are great when you’re just starting and when you’ve become used to building muscle on the ketogenic diet. The act of lowering and raising the body using your arms trains the chest muscles and triceps. It is a form of resistance training workout and has been proven to improve upper body muscle strength .
Pull up is a high strength and muscle building exercise that focuses primarily on your back, shoulders, and arms. It also strengthens your mental focus as you hold on to the bar. Bodybuilding experts consider pull-ups as one of the ultimate upper body muscular workouts there is.
Reverse curls are great for not only bicep training but also to promote bigger arm muscles.
Great for building and strengthening the back and forearm muscles.
This is a classic keto meal that you can eat even if you weren’t looking to build any muscles, but it will turn out to be a big plus for those who are. It is also one of the easiest, simplest, and most satiating keto recipes you’ll ever come across.
Drop two tablespoons of butter into the pan on medium heat, next to the beaten eggs, and then the spinach. Season with salt and pepper and sprinkle some cheddar cheese on top. Add half an avocado to the side, and there you have it - a delicious meal with the right amount of proteins, carbs, and fats to get you going with the muscle building.
If you make this recipe with six eggs, 2 tbsp butter, 2 tbsp cheese, 1 cup of spinach, and ½ avocado, the total calories will be roughly 672. You can adjust the ingredients to suit your taste or if you want to modify the total macros.
Macros per serving:
Fat: 62.7 g; Carbs: 11.9 g; Protein: 19.5 g
This is another quick and easy recipe to get some healthy fats before or after working out. It calls for five simple ingredients: salmon fillets with skin, salt, sake, white wine, and miso. The cooking time for this recipe is 25 minutes and yields four servings. You can add ½ an avocado for some extra dose of fat if you want.
Macros per serving:
Fats: 9.23 g; Protein: 28.38 g; Carbs: 1.03 g
This recipe will be a treat for steak lovers. It calls for six simple ingredients (excluding the onion): butter, ribeye steaks, broccoli, tamarind soy sauce (optional), pumpkin seeds, and salt & pepper. It’s a super simple recipe with a generous amount of healthy fats and protein to support your muscle building exercise.
Macros per serving:
Fats: 75 g; Carbs: 10 g; Protein: 40 g
Here’s another power-packed keto meal. The main ingredients of this recipe are deli roast beef, cheddar cheese, avocado, mayonnaise, lettuce, olive oil, salt, and pepper. It also calls for radishes, Dijon mustard, and scallion which you can skip or keep depending on your taste buds. This recipe yields two servings.
Macros per serving:
Calories: they don’t recommend calorie counting.
Fats: 98 g; Carbs: 6 g; Protein: 38 g
This is a super filling and easy chicken recipe that calls for boneless chicken breast, low carb keto breadcrumbs, deli ham, and swiss cheese. It also includes the ingredients and recipe for the Malibu sauce and crumb toppings. The total cook time including the prep time is 40 minutes, and it yields four servings.
Macros per serving:
Fats: 55 g; Carbs: 4 g; Protein: 46 g
Contrary to the popular myth, carbs aren’t crucial for muscle building and maintenance. The little bit of carbs you think you need will come from glycogen storage when some of the protein you eat get converted into glycogen via a process called gluconeogenesis.
Also, as discussed earlier, you do not need to load up on proteins to build muscles. In the studies we discussed, you can see how going above 20 g of protein after resistance training failed to enhance protein synthesis any further despite the availability of extra amino acids. The study also showed how maximal protein synthesis was achieved at 20 g of protein intake.
The ketogenic diet has been found in some cases to be more effective than the standard western diet for muscle building and fat loss. Ketones bodies prevent the breakdown of muscle mass and promote protein synthesis by saving the use of BCAAs (branched chain amino acids).
Resistance training is one of the best ways to build muscle on a keto diet because it activates the muscle satellite cells by making them think that the muscle cells are under trauma. The satellite cells fuse and multiply with muscle fibers to repair and form new muscle protein strands.
It’s important to make sure you stay hydrated and watch out on your electrolytes to avoid keto flu symptoms. You can do that by sipping on some salt water throughout the day and adding generous sea salt or Himalayan salt to your salads. Eating avocados and drinking coconut water will also help replenish potassium.
Don’t jump on resistance training workouts without proper research and guidance.