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How much protein do I need to build muscle?


Protein is an essential macronutrient responsible for the growth, repair, and recovery of muscle tissue. When combined with resistance training, protein can enhance the rate of muscle building in both males and females to obtain a more aesthetically pleasing physique and increase physical performance.

However, how much protein we need to gain muscle mass is often debated and may be decided on several factors.

In this article, we will review protein in depth and discuss the optimum quantity, frequency, timing, and type to maximise muscle building.

During exercise, we cause small micro tears to muscle fibres, which are effectively ‘damaged’ through the nature of training, this is known as ‘muscle breakdown’. Protein consists of amino acids which are building blocks for muscle tissue, we use these amino acids from the protein we consume to repair and rebuild damaged muscle fibre as a result of training, this is known as ‘muscle protein synthesis’.

In order to gain muscle tissue, we must retain a positive protein balance by synthesising more protein than we break down which therefore explains the importance of protein consumption for growth and repair.

Quantity - How much protein is required to build muscle?

Well, multiple studies suggest that a daily protein intake of 1.6 – 2.2 grams per kilogram of body weight is optimal for muscle growth. For example, a person who weighs 80kg should consume between 128 – 176 grams of protein daily to maximise muscle-building potential.

It is worth noting that this recommendation is based on a range rather than a specific number and other individual factors such as gender, age, body composition, physical activity level, training status and stimulus may heavily influence how effectively individuals respond to the 1.6 – 2.2 grams per kilogram recommended range.

For example, older adults may require a higher protein intake to maintain muscle mass, while athletes with frequent high-level training and competition may need higher protein requirements to support muscle recovery and growth. These individual factors are all case-dependent but also play a role genetically irrespective of health status or lifestyle choices. 

A study published in the International Journal of Nutrients comparing protein requirements between males and females showed a protein intake of 1.6 grams per kilogram was adequate to support muscle protein synthesis for both genders, however, males displayed a significantly greater rate of protein synthesis. The study also concluded that females showed a greater rate of whole-body muscle breakdown which suggests that females may require a slightly higher protein intake to maintain or build muscle mass compared to males.

Frequency - How often should I consume protein?

Research widely suggests a consistent protein intake at various intervals throughout the day promotes more potential for muscle building as opposed to consuming one large amount of protein in a single meal. This is because our bodies are limited to how much protein we can absorb and utilise in one given hit. Research shows that protein amounts of 20-40 grams are sufficient to stimulate muscle protein synthesis at an optimised rate for 3-4 hours. However, amounts in excess of 40 grams may be appropriate for larger individuals who need a higher intake of protein to activate muscle protein synthesis as achieving this is usually correlated to bodyweight. These frequent muscle protein synthesis hits are responsible for supporting muscle growth and are equally if not more important than the overall protein intake itself, because multiple triggers of muscle protein synthesis automatically contribute to an accumulation towards the overall protein intake. However, one large consumption of protein cannot be as effective for muscle building regardless of the total amount because triggering muscle protein synthesis is greatly limited and reduced. Therefore, it is recommended generally that individuals consume 20-40 grams of protein per serving every 3-4 hours to maximise muscle building potential depending on their individual needs and goals.

Timing - Does the timing of consuming protein matter?

Yes, as discussed 3-4 hours is the optimum timing of protein intake to contribute to a positive protein balance. However, it is also well known that consuming protein after exercise may influence muscle growth.

Research suggests that consuming 20-40 grams of protein within 60 minutes post-exercise may be the best time to maximise protein synthesis. This timeframe is known as the ‘anabolic window’ and is where the body is most responsive to protein intake. The timing of protein intake during this window is important because the damaged muscle fibre requires sufficient protein intake to stimulate muscle protein synthesis for recovery and growth.

A study published in the Journal of Clinical Nutrition showed that 20 grams of protein consumption immediately post-exercise resulted in more effective muscle protein synthesis compared to 20 grams consumed 3 hours after exercise. Furthermore, protein shakes such as Critical Whey and Critical Mass Lean Mass Gainer are effective and beneficial sources of protein post-exercise for quick and easy absorption with optimal quantities in each serving.

Type - Does the type of protein matter?

Yes, the quality of protein can impact the rate of muscle growth. As highlighted above, proteins are made up of amino acids which are the building blocks for muscle tissue.

Amino acids can be categorised as either ‘complete’ proteins or ‘incomplete’ proteins. Complete proteins are considered higher quality because they contain all the essential amino acids that the body needs to build muscle tissue, however, the body cannot produce these essential amino acids, so they need to be obtained through diet. Sources of complete proteins stem mainly from animal-based foods such as meat, fish, eggs, poultry, dairy, and whey.

Incomplete proteins like many plant-based sources are missing one or more essential amino acids and therefore vegans or vegetarians may sometimes struggle to get adequate protein intake for muscle building. It is however important to note that specific incomplete proteins such as rice and peas can be combined to make a complete protein source.

However, eating incomplete proteins directly post-exercise may not be optimal for muscle building within the anabolic window as discussed earlier due to the volume of food and a slower digestion rate. Therefore, protein powders specifically for vegans and vegetarians such as Critical Plant and Clear Vegan Protein have been formulated for quick absorption whereby an ideal blend of plant-based protein sources are combined to obtain a complete amino acid profile to promote maximum protein synthesis.

In summary...

Protein intake is essential for maintaining and building muscle mass. The recommended amount is somewhere between 1.6 – 2.2 grams per kilogram of body weight per day in regular servings amongst 20-40 grams every 3-4 hours to optimise muscle-building potential by frequently triggering muscle protein synthesis. However, it is important to remember protein requirements and recommendations may vary based on individual factors such as age, gender, physical activity level, body weight, body composition, training status and stimulus.

Timing and quality of protein are also important to consider with complete protein sources including a full amino acid profile proving to play a role in maximising muscle protein synthesis, especially around exercise, particularly within the ‘anabolic window’ which is typically 60 minutes post-exercise.

Generally, a well-balanced diet which includes frequent and sufficient protein consumption from quality sources combined with regular exercise (specifically resistance training) can support muscle recovery, repair, and growth as well as contributing to the overall maintenance of health and wellbeing.


Written by Kevin Poole MSc, BSc

4x PT of the Year, Fitness Expert & Educator, Transformation Specialist

Instagram - @kevinpoolefitness



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