Will Ketosis Impact Your Muscle Mass?


In recent years, the ketogenic diet has gained popularity for its potential to promote weight loss and improve overall health. However, concerns about its impact on muscle mass have left many fitness enthusiasts questioning whether ketosis is a friend or foe when it comes to maintaining muscle. In this blog post, we'll explore the relationship between ketosis and muscle mass to help you make an informed decision about adopting this low-carb, high-fat diet.


Understanding Ketosis

Before delving into the effects on muscle mass, let's briefly understand what ketosis is. The ketogenic diet is a low-carbohydrate, high-fat eating plan that induces ketosis, a metabolic state where the body relies on ketones, derived from fat, as its primary source of energy instead of glucose from carbohydrates. This shift in energy metabolism has been linked to various health benefits, including weight loss and improved insulin sensitivity.


The Concerns About Muscle Mass

One of the primary concerns surrounding ketosis is its potential impact on muscle mass. Carbohydrates, particularly glycogen derived from them, play a crucial role in fueling high-intensity exercise and supporting muscle growth. With the limited intake of carbohydrates on a ketogenic diet, skeptics worry that the body may break down muscle protein for energy, leading to a loss of muscle mass.


Photo by Scott Webb on Unsplash


Ketosis and Muscle Preservation

Contrary to concerns, emerging research suggests that ketosis may not necessarily lead to muscle loss. In fact, some studies propose that the ketogenic diet could be muscle-sparing under certain conditions. When the body is in ketosis, it becomes highly efficient at using fat for energy, which can help preserve muscle protein. Additionally, the increased intake of dietary protein on a ketogenic diet may contribute to muscle maintenance and repair.


Ketosis and Protein Needs

To maintain muscle mass during ketosis, it's important to meet your minimum daily protein intake. The Recommended Dietary Allowance (RDA) for protein is 0.8 grams per kilogram of body weight daily. An overall daily protein intake in the range of 1.4–2.0 g protein/kg body weight/day (g/kg/d) is sufficient for most exercising individuals.


Protein-rich whole foods like meat, fish, eggs, dairy and veggies should be prioritized to easily meet this optimum protein range while in ketosis for muscle preservation.


Preserving Muscle Through Resistance Training

Diet alone cannot build muscle mass - exercise is required too. Lifting weights through resistance training stimulates muscle protein synthesis which supports muscle growth and maintenance.


Pairing ketosis with resistance training provides the optimal muscle preservation strategy. In one study, athletes on low-carb diets lost no performance and gained the same muscle mass as those on normal carb diets over 2 months while training.


Photo by Sam Moghadam Khamseh on Unsplash


For non-athletes, simply incorporate bodyweight exercises, yoga, calisthenics, weightlifting or classes 2-3 times weekly while in ketosis for muscle support and growth. Consistent training ensures your muscles are not breaking down.



Objectively Tracking Your Keto-Adaptation with Sibiosensor

The SiBio KS1 Continuous Ketone Monitoring (CKM) System allows tracking your ketone levels throughout the fat adaptation process. By wearing the waterproof sensor and viewing real-time readings via the SiBio CKM App, you can gain valuable insights into how your body responds metabolically to exercise at different stages of keto-adaptation. This personalized data will help optimize your training program to preserve muscle mass most effectively while achieving fat loss goals in ketosis over time.


In summary, the research shows that ketosis alone does not inherently lead to muscle loss when protein needs are met. By combining a ketogenic diet with resistance training and monitoring your metabolic adaptation and ketone levels using the SiBio KS1 Ketone Monitor, you can transition safely into ketosis and maintain muscle mass for performance and appearance goals alike. Overall, various studies indicate ketosis is compatible with an active lifestyle when the right strategies around food, exercise and supplementation are applied.



Q: Can you build muscle on keto?

A: Yes, it is possible to build muscle while following a ketogenic diet. Adequate protein intake, coupled with resistance training, can stimulate muscle protein synthesis and promote muscle growth. While carbohydrates are typically associated with muscle building due to their role in glycogen replenishment and insulin release, ketosis can still support muscle growth through protein metabolism and anabolic signaling pathways.

Q: How does ketosis help athletes?

A: For many athletes, ketosis can provide an alternative fuel source in fat to spare precious glycogen stores. It may also enhance endurance and support recovery between training sessions. Some research indicates athletic performance is maintained or improved for some athletes once fat-adapted to ketosis.

Q: How much protein to build muscle?

A: The amount of protein needed to build muscle varies depending on factors such as body weight, activity level, and training intensity. An overall daily protein intake in the range of 1.4–2.0 g protein/kg body weight/day (g/kg/d) is sufficient for most exercising individuals.

Q: Which protein absorbs the best?

A: Whey protein is quickly digested and absorbed, making it a fast-acting protein source. Casein protein has a slower, more sustained release profile. For building muscle, a blend of whey and casein provides balanced fast and slow-released amino acids. Egg and meat proteins also absorb well.

Q: Which is the faster acting form of protein?

A: Whey protein isolate is considered the fastest absorbing form of protein. Its soluble characteristics allow for rapid uptake and delivery of amino acids to muscles post-workout. This makes whey highly beneficial for muscle protein synthesis and repair when timing protein intake around exercise.

Q: Can I combine ketosis with intermittent fasting for muscle preservation?

A: Yes, combining ketosis with intermittent fasting may enhance muscle preservation and promote fat loss. Intermittent fasting can help increase ketone production and stimulate autophagy; a process that may help preserve lean muscle mass while in a calorie deficit.