Choosing a Protein Supplement for Strength and Muscle Mass

Which protein supplement is best? This is a very common question for those people wanting to build strength or muscle mass. Recently, a meta-analysis was published which explored the role of protein in building strength and muscle mass. I explore some of their findings below.

Will protein help me get stronger and build muscle mass?

Yes it will, but it is important to look at the extent to which protein (both food and supplements) contribute to changes in strength and muscle mass.

Building Strength

Across all of the included studies, protein intake was associated with a 9% gain in 1 repetition maximum strength. That is, participants, on average, increased the amount they could lift by 27kg over the course of the included studies. However, analyses demonstrated that only 2.49kg of this 27kg was attributable to their protein intake. So, if you are looking for gains in strength, consider whether the extra 9% is significant to you. It may not be worth the effort for the average gym member just looking to increase strength, however it may be worth the effort for the competitive weight-lifter.

Building Muscle Mass

Across all of the included studies, protein intake was associated with a 27% increase in fat free mass (which includes muscle tissue). This means that on average, participants increased their fat free mass by 1.1kg over the course of the included studies. Analyses demonstrated that 0.3kg of this 1.1kg was attributable to their protein intake. Thus, if you are looking to gain muscle mass, protein intake should be a key consideration for the average gym member and body builder alike.

Protein supplements are unlikely to contribute substantially to increases in strength, however they are likely to contribute substantially to increases in muscle mass.

Do you have to take protein supplements to get stronger or build muscle mass?

This one is easy. No. Analyses demonstrated that it really doesn’t matter whether you get your protein from food or supplements.

Some good reasons to use food as a protein source include:

  • It is nutrient dense, so alongside your dose of protein, you will be getting a good dose of other beneficial nutrients.

  • Food can be more affordable than supplements.

Conversely, a good reason to use a protein supplement is:

  • It is more convenient to carry around a protein shake than a container of food.

So, do whatever works for you!

It doesn’t matter whether you consume protein as food or supplements. Both will increase your strength and muscle gains.

What is the optimal dose of protein?

Analyses demonstrated that increases in fat free mass were optimal at a dose of 1.62g protein per kilogram of body weight per day, with the authors suggesting that daily protein intakes of up to 2.2g protein per kilogram of body weight per day might be suitable for people looking to take the most advantage of protein supplementation. Based on previous data, we know that splitting your protein dose up across the day is associated with larger increases in muscle strength and muscle mass, so the recommendation is still to consume around 4 doses of 0.25g protein per kg bodyweight over the course of the day, as well as a larger dose of 0.5g protein/kg body weight at night.

Interestingly, increases in strength were not affected by differences in daily protein intake, so a similar recommendation may be able to be applied across this population.

Remember, any time you increase the amount of protein in your diet you start to offset the contribution of carbohydrate and fat into your diet, which needs to be considered. Make sure you are still getting your recommended requirements of carbohydrates and fats.

Look for a protein supplement which provides approximately 0.25 grams of protein per kilogram of body weight per serve. Consume this dose every four hours or so, with double the dose at night.

Leucine dose

Research suggests that of all the amino acids, leucine appears to stimulate muscle protein synthesis. Although an exact dose is not known, it is generally recommended that each dose of protein throughout the day should contain around 3g of leucine.

Look for protein supplements which provide approximately 3g of leucine per serve.

Which protein source?

There are many different sources of protein available to you, from animal sources through to plant sources.

As a general rule, soy or whey are your best options during the day, and soy or casein are your best options at night. See below for a breakdown of the options.

When comparing the different types of proteins we need to look at two factors:

  1. Whether the protein source contains enough of all of the essential amino acids

  2. Whether the protein source is digestible

To assess these two factors together, a score, known as the PDCAAS score, is given to foods. This score is affected by the essential amino acid content and the digestibility of the protein. That is, foods which have fewer essential amino acids, and which are less digestible receive a lower PDCAAS score than those with more essential amino acids and which are more digestible. The highest PDCAAS score a food or protein supplement can receive is 1.0, and the lowest 0.0. Generally animal sourced foods and protein supplements have higher PDCAAS scores than plant-based foods and protein supplements.

Note that refining of the protein source can affect its digestibility. This means that hydrosylates and isolates of the below protein sources may be more digestible and have a higher PDCAAS score than those stated below. In general, isolates are the more refined and most digestible sources, and are preferable.

Whey

  • Whey contains all 9 essential amino acids

  • Whey is a high-quality protein source with a PDCAAS score of 1.0

  • Whey is rapidly absorbed into the bloodstream

  • Whey is the most highly researched of all of the protein supplements

  • Analyses suggest that whey is as effective as soy at increasing muscle mass and strength

Casein

  • Casein contains all 9 essential amino acids

  • Casein is a high-quality protein source with a PDCAAS score of 1.0

  • Casein is more slowly absorbed into the bloodstream, making it an optimal choice for your night-time dose of protein.

  • Some research has been conducted on casein

Beef

  • Beef contains all 9 essential amino acids

  • Beef is a high-quality protein with a PDCAAS score of 0.92

  • There have been no high-quality studies conducted on supplemental beef protein, only one study conducted on beef as a food

Egg

  • Egg contains all 9 essential amino acids

  • Egg is a high-quality protein with a PDCAAS score of 1.00

  • There have been no high-quality studies conducted on supplemental egg protein on its own, only as part of a protein blend.

Soy

  • Soy contains all 9 essential amino acids, however it is a little low in the amino acids Methionine, Cysteine and Lysine

  • Make sure to consume other sources of protein across the day to fill in the essential amino acid gaps

  • Soy is nevertheless a high-quality protein with a PDCAAS score of 0.97

  • There have been several studies conducted on soy protein

  • Analyses suggest that whey is as effective as soy at increasing muscle mass and strength

Pea

  • Pea contains all 9 essential amino acids, however it is a little low in the amino acids Methionine and Cysteine

  • Make sure to consume other sources of protein across the day to fill in the essential amino acid gaps

  • Pea is a fairly high-quality protein, with a PDCAAS score of 0.86

  • There has been one high-quality study conducted on pea protein

Rice

  • Rice contains all 9 essential amino acids, however it is very low in the amino acid Lysine

  • Make sure to consume other sources of protein across the day to fill in the essential amino acid gap

  • Rice is a fairly low-quality protein, with a PDCAAS score of 0.38

  • There have been no high-quality studies on rice protein

Whey or soy are the best options during the day, casein or soy are the best options at night.

Trial and error

Of course, it is never so simple to find what works for you. Indeed, protein supplements often contain other ingredients which may be relevant to you, and which will help guide your selection too.

Keep experimenting with different products, protein sources and doses until you find the one that works for you.

References

Morton RW, Murphy KT, McKellar SR, Schoenfeld BJ, Henselmans M, Helms E, Aragon AA, Devries MC, Banfield L, Krieger JW, Phillips SM. A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength in healthy adults. Br J Sports Med. 2018 Mar;52(6):376-384. doi: 10.1136/bjsports-2017-097608. Epub 2017 Jul 11. Review. PubMed PMID: 28698222; PubMed Central PMCID: PMC5867436. 

Hoffman JR, Falvo MJ. Protein - Which is Best? J Sports Sci Med. 2004 Sep 1;3(3):118-30. eCollection 2004 Sep. Review. PubMed PMID: 24482589; PubMed Central PMCID: PMC3905294. 

Rutherfurd SM, Fanning AC, Miller BJ, Moughan PJ. Protein digestibility-corrected amino acid scores and digestible indispensable amino acid scores differentially describe protein quality in growing male rats. J Nutr. 2015 Feb;145(2):372-9. doi: 10.3945/jn.114.195438. Epub 2014 Nov 26. PubMed PMID: 25644361.