Protein Supplementation

There is probably no other nutrient that gets as much attention with sports people more as protein owing to its role in muscle growth and repair. Protein is found in foods such as red meat, poultry, fish, dairy, eggs, nuts, tofu and legumes but is also available in a variety of formulated supplements drinks, bars and powders. For some, protein supplements can be helpful as part of their overall nutrition plan, however they certainly aren’t essential for everyone.

Do you need extra protein?

Endurance athletes in heavy training, athletes trying to gain muscle mass and strength athletes in initial stages of training all have protein needs higher than the general, non-exercising population. Most athletes will easily reach their daily total protein targets with their usual eating habits however, those who follow vegetarian or vegan diets or do not consume dairy foods may have difficulty meeting protein requirements if they are not well planned. It is advised that these athletes consult an Accredited Sports Dietitian to make sure they’re hitting their appropriate protein targets.

Does the type of protein matter?

The nutritional value of a protein is determined by its unique amino acid profile – proteins with a high biological value (HBV) are recommended wherever possible. Animal based proteins such as dairy foods, eggs, meat, fish and poultry as well as isolated soy protein are considered HBV proteins as they contain all of the essential amino acids needed by the human body. Plant based proteins only contain only some of the essential amino acids are considered to be of lower biological value.

Leucine, a branched chain amino-acid, plays a critical role in ‘switching on’ muscle protein synthesis. The leucine content of foods varies but some foods are naturally high in leucine, including milk (and whey protein) and red meat. Research suggests that ~2-3g of leucine maximally stimulates protein synthesis (equivalent to ~20-25g of HBV protein).

Does the timing of protein intake make a difference?

Research suggests each time protein is consumed there is a small spike in muscle synthesis with 20-25g of HBV protein producing a maximal response. Eating quantities in excess of this amount, offers no further benefit to muscle protein synthesis. Spreading protein across the day by including it in meals and snacks will produce multiple spikes in muscle protein synthesis. Eating protein in the hour following exercise can help to prolong the protein synthesis response to exercise, helping to promote muscle gains and minimise muscle breakdown (losses).

Are supplements necessary?

The decision to use a protein supplement should be based on several issues relevant to the individual, including their training load, goals, daily energy requirements, typical diet, appetite post-exercise, budget available and general dietary intake. Talking with an Accredited Sports Dietitian can help to establish if the use of a protein supplement is necessary.  It is also important to continue to re-evaluate the need for supplementation when changes to training etc. occur.

What is the difference between different protein powders?

The range of protein and amino acid supplements available can be quite confusing. Protein supplements can be broadly classified according to their nutrient profile as either providing protein only (as a single protein source or a protein blend i.e. combination of several proteins). There are also supplements which contain a combination of protein and carbohydrates. Some supplements also have additional ergogenic ingredients such as creatine, specific amino acids, proposed fat metabolisers, vitamins and minerals.

Whey Protein

A HBV protein that is rapidly digested. Whey is rich in branched chain amino acids (BCAAs), especially leucine. There are 3 main forms of whey protein:

  • Whey Protein Concentrate (WPC) – Typically 70-80% protein by weight with small amounts of lactose (milk sugar) and fat. Cheaper than whey protein isolate
  • Whey Protein Isolate (WPI) – Powder is usually 90% protein by weight, with negligible amounts of carbohydrates (lactose) and fat
  • Whey Protein Hydrolysate (WPH) – Derived from WPC or WPI and characterised by shorter peptides or amino acid chains, supposedly resulting in even more rapid digestion but evidence to date is conflicting.


A HBV protein found in milk. Casein clots in the acidic environment of the stomach, resulting in slower digestion and delivery of amino acids to the body.

Soy Protein

A HBV, rapidly digested protein. Available as both a soy concentrate and soy isolate. It is often used in mixed protein supplements and protein bars.

Egg Albumin

A high quality protein source that is free of fat and carbohydrate. It is more expensive than whey and casein protein.

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