The role protein plays in building lean muscle mass and strength.
Dr. Crionna Tobin, PhD, Optimum Nutrition In-house Nutrition Expert
Muscle growth or ‘hypertrophy’ is one of the main reasons why people train, but what does it actually mean and how does protein support this process?
Traditionally, an increase in muscle mass was a training outcome desired predominantly by those who wanted to increase muscle size and bulk. However, muscle strength, which is a consequence of increased lean muscle mass, is critical for every athlete to optimise performance from the ballerina to the sprinter, to the team sports player.
Growing lean muscle mass, which is also known as hypertrophy, is stimulated by resistance training. Fundamentally it is the volume and intensity of this type of training that increases the size and strength of the muscle providing the athlete with more power to dance, run, jump, box, tackle or to simply lift more weight. Although this process is regulated predominantly by exercise feeding protein around training plays a critical role in complimenting this process as it provides the muscle with the building blocks to increase this lean muscle mass.
The process of increasing skeletal muscle mass occurs due to a process known as muscle protein turnover, which is a balance between the muscle’s ability to grow, also known as muscle protein synthesis (MPS) and muscle protein breakdown (MPB). This process of MPS and MPB fluctuates throughout the day, the balance of the two processes ultimately determining whether the body, maintains, grows or loses lean muscle mass. When MPS is greater than MPB a positive protein balance is achieved leading to muscle growth, whereas when MPB exceeds MPS, the muscle breakdowns over time leading to atrophy or muscle wasting. A combination of resistance or strength training and protein feeding stimulates hypertrophy whereas inactivity during periods without training or injury combined with a low energy intake contributes to the loss of muscle mass.
How does training build lean muscle mass?
Training damages the muscle fibres used during the training session. The degree to which they are damaged depends on how accustomed the athlete is to the training session, the intensity of the training session and its duration. This muscle damage which may cause muscle soreness after exercise is essential for muscle growth. The muscle needs to be damaged in order to facilitate breakdown and the ultimate rebuilding of the muscle into a larger and stronger tissue. In fact even though resistance training increases MPS 100% above resting levels the increase in muscle breakdown which occurs simultaneously prevents the muscle from optimally growing and repairing after exercise. This is where the role of protein is critical during the recovery period. Feeding the body with high quality protein such as whey protein around exercise provides the body with the building blocks to further increase MPS and reduce MPB thereby increasing muscle growth and repair to a far greater extent than either training or protein feeding alone. Feeding the body with protein around exercise optimises the recovery of the muscle.
The role of protein in supporting muscle growth
Protein provided to the body is essential in the recovery period to provide the muscle with the building blocks to support muscle growth. In the recovery period immediately after exercise (within 30-90 minutes) the muscle is far more sensitive to protein and therefore providing the muscle with high quality protein, such as Optimum Nutrition Gold Standard 100% Whey™ Protein at this time will optimise muscle recovery.
Consuming whey protein around exercise is a superior option to support the growth and repair of muscle mass as it is delivered to the muscle fast and contains a high quantity of BCAAs (brand chain amino acids) particularly leucine. Leucine acts as a trigger to switch on MPS stimulating muscle growth as soon as it reaches the muscle. However, it is important to understand that all the rest of the amino acids present in whey protein are essential to prolong muscle growth during the recovery period maximising muscle growth and repair.
Research has found that consuming a dose of 0.3g per kilogram of body weight, which usually equates to 20-40g of protein, is optimal to support the growth and repair of the muscle after exercise. Therefore, if you are 70kg you should consume roughly 21g of Gold Standard 100% Whey™ Protein (0.3g x 70 kg) to support muscle recovery. It is also well established that athletes or people who exercise regularly require a higher daily protein intake between 1.2-2.3g/kg to facilitate muscle recovery and training adaptations. It is more beneficial for muscle growth to spread protein intake evenly throughout the day in 20-40g doses rather than consume larger doses in one to two meals. Daily protein intakes should come mainly from food, however Gold Standard 100% Whey Protein™ can be used to supplement the diet to help achieve these targets and also provide a convenient and tasty solution to hitting your protein goals after a training session.
Ultimately, protein plays a critical role in supporting the growth and repair of muscle during the recovery period. Each time exercise is performed particularly if that exercise is high volume or intense strength training the muscle is damages and requires protein in order to repair, rebuild and grow bigger and stronger so the athlete can maximise their adaptation to each training session and achieve their performance goals.
Take Home Messages
- Growing lean muscle mass, which is also known as hypertrophy, is stimulated by resistance training
- It is the volume and intensity of resistance exercise that stimulates the increase in muscle mass
- Consuming Gold Standard 100% Whey™ Protein around training, particularly in the recovery period provides the muscle with the building blocks to repair and rebuild the muscle
- Whey protein is the superior choice of protein to consume after exercise as it is fast-acting and contains leucine
- Consuming 0.3g/kg, or 20-40g of protein 30-90 minutes after exercise will contribute to optimising recovery
- Athletes require a protein intake of between 1.2-2.3g or protein per kg of body mass which should be consumed evenly throughout the day in doses of between 20-40g of protein
Stokes et al 2018. Recent Perspectives Regarding the Role of Dietary Protein for the Promotion of Muscle Hypertrophy with Resistance Exercise Training. https://www.ncbi.nlm.nih.gov/pubmed/29414855
Jager R., 2017. International society of sports nutrition position stand: Protein and exercise.
Cermak, NM et al., 2012. “Protein Supplementation Augments the Adaptive Response of Skeletal Muscle to Resistance-Type Exercise Training: A Meta-Analysis