Should I avoid carbs to build muscle? Experts say no

October 16, 2025 •

4 min read

Contrary to the popular misconception, carbohydrates are a cornerstone of effective muscle-building, not an enemy to be avoided. In fact, adequate carb intake is non-negotiable for anyone serious about optimizing their workouts and maximizing muscle growth.

Quick Summary

This article explains why avoiding carbohydrates is counterproductive for building muscle. It details how carbs provide the essential energy for intense training, spare protein for muscle repair, and accelerate post-workout recovery by replenishing glycogen stores.

Key Points

Carbs Fuel Intense Workouts: Stored as muscle glycogen, carbohydrates are the primary fuel for high-intensity resistance training.
Spare Protein for Muscle Repair: Sufficient carb intake prevents the body from using valuable protein for energy, allowing it to be used for muscle synthesis instead.
Optimize Post-Workout Recovery: Consuming carbs with protein after a workout efficiently replenishes glycogen stores, accelerating recovery and preparing muscles for the next session.
Support Hormonal Balance: Adequate carb intake helps regulate hormones like insulin and cortisol, creating a more anabolic (muscle-building) state.
Enhance Training Volume: Proper carbohydrate availability helps prevent fatigue, enabling you to train harder and longer, which is critical for muscle growth.
Informed Choice is Key: The focus should not be on avoiding carbs but rather on choosing the right types and timing their intake strategically for maximum benefit.

The Core Role of Carbohydrates in Muscle Building

Many fitness enthusiasts harbor a long-held belief that cutting carbohydrates is the key to achieving a lean, muscular physique. However, overwhelming scientific evidence and expert consensus confirm that this approach is flawed for those looking to build significant muscle mass. The body's primary fuel source for high-intensity exercise, such as weightlifting, is glucose, which is derived from the carbohydrates we consume. When you eat carbohydrates, they are broken down into glucose and stored in your muscles and liver as glycogen. These glycogen stores are critical for fueling your body through demanding workouts. Without sufficient glycogen, your performance will suffer, leading to less intense training sessions and, consequently, limited muscle growth.

Why You Shouldn't Fear Carbs for Muscle Growth

Instead of fearing carbohydrates, it's more beneficial to understand their pivotal role in the muscle-building process. Here’s why strategically including carbs in your diet is the better approach:

Fuel for Performance: Without adequate carbs, your body's glycogen stores run low, resulting in fatigue and a drop in training intensity. This compromises your ability to lift heavy and push through those final, crucial reps necessary for stimulating muscle hypertrophy.
The Protein-Sparing Effect: When carbohydrate intake is insufficient, the body can resort to using protein for energy, a process known as gluconeogenesis. This diverts protein away from its primary function of repairing and building muscle tissue. By consuming enough carbohydrates, you ensure that the protein you eat is dedicated to muscle synthesis.
Optimized Recovery: Post-workout, your muscles are highly sensitive to insulin, a hormone triggered by carbohydrate intake. Consuming carbs immediately after training helps replenish depleted muscle glycogen stores quickly, speeding up the recovery process. This rapid replenishment is vital, especially if you have multiple training sessions throughout the day.
Hormonal Balance: Low-carb diets can lead to increased cortisol levels, a stress hormone that promotes muscle breakdown. By maintaining a balanced intake of carbohydrates, you help keep cortisol in check and support an anabolic (muscle-building) hormonal environment.

Comparison: Low-Carb vs. Moderate-to-High Carb Diets for Muscle Building

Choosing the right diet for muscle growth can be confusing, with different approaches promising various results. Below is a comparison to clarify the differences, particularly for resistance training athletes.


Feature	Low-Carb Diet	Moderate-to-High Carb Diet
Primary Energy Source	Fats (in ketosis) or Protein	Carbohydrates (Glycogen)
Workout Performance	May experience reduced stamina and intensity, especially during initial adaptation	Provides reliable, fast energy for high-intensity, heavy lifting
Glycogen Replenishment	Inefficient and slow, relying on gluconeogenesis	Fast and efficient, promoting quicker recovery
Protein Sparing	At risk of using protein for energy, which hinders muscle repair	Protects protein stores, allowing for maximum muscle synthesis
Insulin Response	Lower insulin response	Stimulates insulin release, which aids nutrient transport to muscles
Hormonal Environment	Can lead to elevated cortisol levels, potentially hindering growth	Supports a more stable hormonal environment conducive to growth

How to Strategically Incorporate Carbs

Rather than avoiding carbs, the goal is to be strategic about the types and timing of your intake. Here are some practical tips for incorporating carbohydrates into your muscle-building diet.

Choose the Right Types of Carbs

Not all carbohydrates are created equal. The key is to balance different types to fuel your body effectively throughout the day.

Complex Carbohydrates These provide a steady, sustained release of energy and are packed with fiber, vitamins, and minerals. Examples include oats, quinoa, brown rice, sweet potatoes, legumes, and whole-grain bread and pasta.

Simple Carbohydrates These are useful for a quick energy boost, especially around your workout window. Examples include bananas, white rice, sports drinks, and dried fruit.

Timing Your Carbohydrate Intake

To maximize performance and recovery, timing is key:

Pre-Workout (60-90 minutes before): Consume a meal with complex carbohydrates and moderate protein to top off glycogen stores.
Post-Workout (within 30-60 minutes): This is ideal for simple carbs to quickly replenish muscle glycogen, especially with protein.
Throughout the Day: Spread remaining carb intake across meals for stable energy.

Carb Cycling: An Advanced Strategy

Carb cycling involves alternating high-carb days with low-carb days, which can help maximize muscle gain and manage body fat for some individuals. This requires careful planning and for most, a consistent moderate intake is sufficient.

For more in-depth nutritional guidelines, the International Society of Sports Nutrition provides excellent resources on the role of nutrition for athletes.

Conclusion

Avoiding carbohydrates is not the optimal approach for serious muscle building. Carbs are essential for fueling intense workouts, preserving protein for muscle repair, optimizing recovery, and supporting a favorable hormonal environment. A strategic approach focusing on the right types and timing of carbohydrates is key to achieving lasting muscle growth.

Frequently Asked Questions

While it is possible to build some muscle on a very low-carb diet, it is less efficient and can be more difficult. Carbohydrates are the body's preferred fuel for intense exercise, and their absence can lead to lower training performance and a greater risk of muscle protein being used for energy.

For those engaged in regular, intense training (5+ hours per week), a general recommendation is 5-7 grams of carbohydrates per kilogram of body weight per day. Individual needs can vary based on factors like metabolism, training intensity, and body weight.

For most of the day, prioritize complex carbohydrates like whole grains, starchy vegetables, and legumes for sustained energy. Simple, fast-digesting carbs like fruits or white rice are best used immediately post-workout to quickly replenish glycogen stores.

Yes. Consuming carbohydrates before a workout ensures you have sufficient energy, while consuming them afterward helps replenish depleted muscle glycogen and aids recovery. Pairing post-workout carbs with protein is particularly effective.

Eating carbs does not inherently cause fat gain. Weight gain is a result of consuming more calories than you burn. When managed within your total daily caloric intake, carbohydrates provide fuel without leading to excess fat storage.

If your carb intake is too low, you may experience reduced energy levels, poor workout performance, and a slower recovery. Insufficient carbs can also cause elevated cortisol, a hormone that promotes muscle breakdown.

Carb cycling is a dietary strategy where you alternate between higher carbohydrate intake on intense training days and lower intake on rest days. This method can be used to manage fat gain while maximizing performance during workouts, though it requires careful planning.