Updated: Dec 31, 2018
Definitions: MPS = Muscle protein synthesis
Muscle protein synthesis is the process of building specifically muscle protein. - Jorn Trommelen
Choose Quality Protein Sources
3-4g of leucine present in the protein source maximises MPS.
A source containing all of the essential amino acids would be most optimal e.g. animal protein
Comparing whey protein to brown rice protein: 20g serving of whey contains 3g leucine and around 100kcal. 40g serving of brown rice protein contains 3g leucine and around 200kcal.
The calories are not matched. Plant proteins often need to be doubled to reach the leucine threshold. This can be difficult when calories are restricted.
You can check out the protein and leucine content of foods here: http://gmdi.org/Resources/Leucine-and-Protein-Content-of-Foods
2. Consider Protein Timing
MPS has a known refractory period. Every time a large enough dose of protein (with adequate leucine) is ingested there is a 3-5 hour period where MPS levels are elevated, these levels must return to baseline before MPS can be sufficiently stimulated again.
e.g. If you ate a protein rich meal at 8am then ate another at 10am the second meal would not contribute to spiking MPS again. It would likely be stored as glycogen or fat depending on the total nutritional status of the person.
Ideally we want to wait 3-5 hours between each meal to adequately stimulate MPS. We can achieve optimal MPS this simply by eating the correct dosage of protein (with appropriate leucine content) in 3-5 meals per day with 3-5 hour breaks between meals.
3. Determine Your Total Intake
Determine your optimal protein intake for each day then divide this (fairly evenly) across your 3-5 meals. Considering the previous two points we can see that optimal protein intake for person is going to be related to how much protein they need per meal to adequately stimulate MPS.
Factors affecting optimal protein intake:
Gender. The more male a person is the more sensitive they are to amino acids (the things at make up protein). The more female a person is the less sensitive they are to amino acids. This is not in any way related to those who identify male/ female/ non binary.
e.g. if we weight and age matched a male and a female the male would need less protein per lb bodyweight than the female.
Age. We become less sensitive to protein as part of the ageing process so protein intake should naturally increase with time. This doesn’t just apply to those looking to maximise or retain their lean body mass. Adequate protein intake is important for those at risk of age related sarcopenia and other bone loss diseases as well as maintaining work capacity.
Dietary preferences. For a person that eats quality protein sources (based on bioavailability, protein digestibility amino acid corrected score, and amino acid profile) less total protein will be needed to optimise protein intake. For a person who eats less quality protein sources (such as a vegan) the more protein they will be required to eat to optimise their protein intake. This means protein intake, and in turn total caloric intake, will need to be higher for plant based individuals to match protein intake to that of their meat eating counterparts.
Please note: Total daily protein intake takes priority over protein timing. If you aren’t reaching your optimal daily protein intake then trying to implement protein timing is not a worthwhile use of your time yet.
4. Use Whey Protein If You Supplement
Often times more expensive or flashy sounding protein supplements have sub optimal amino acid profiles. Don’t get lured in by bold marketing claims, and always read the label.
Here’s why whey is best:
It has a great amino acid profile i.e. more BCAAs (leucine/isoleucine/valine) and a higher concentration of essential amino acids than all other protein powders.
It does better than casein on satiety, MPS rates, and it keeps blood amino acid levels elevated for longer.
But I thought casein was good?
Well, casein does release amino acids more slowly into the blood stream from the intestines, but it’s actually too slow to raise blood amino acid levels high enough to effectively spike MPS.
Whey is better than egg protein, beef protein, hemp protein, rice protein, pea protein, and soy protein.
Specifically whey protein concentrate is a good, cheap protein option that the manufacturer cannot screw up that badly, still there are some cases where they do *sigh*. If concentrate upsets your gut then switch to isolate which has the amino acid fraction that can upset people (beta lactalbumin) removed. Switching to a stevia sweetened isolate over sucralose or aspartame can also help. Always check the amino acid profile (leucine/isoleucine/valine content) before you buy any protein supplement, if it doesn’t contain the aforementioned 3g leucine per serving, then don’t buy it.
‘You need X amount of protein per day’
Ignore people who say this. Technically, your protein needs are not going to be the same as your optimal protein intake. ‘Needs’ simply refers to what your current body needs to intake to maintain homeostasis (see also: not degenerate and die) and so will likely be a lot lower than your optimal intake. Optimal intake is going to be related to producing optimal performance, aesthetics or health outcomes.
Taking into consideration the previous points in this article we can see clearly that this sh*t’s complicated. There is no one intake that will fit all. A range is a more appropriate suggestion for a coach to give but optimal protein intake is still highly variable.
‘You can only absorb X amount of protein per meal’
Also ignore people who say this. You absorb virtually 100% of everything that enters your gastrointestinal system from your mouth. If you didn’t you’d likely know about it via a bout of post meal diarrhoea.
There are numerous studies showing that when you eat any amount of protein in a meal it all gets absorbed. Absolutely all of it. From a survival standpoint we wouldn't be very efficient creatures if the food we ate didn't get absorbed.
Fun fact: if you want to #science it we actually absorb 110-120% of it as the cells that line the bowel (enterocytes) make proteins themselves (endogenous proteins) which get absorbed too.
So, if you eat 100g of protein per meal, you will absorb it all. It will quite obviously take longer to absorb 100g that 20g, but the rate at which you absorb the first 20g of protein from the 100g will be the same as the rate of 20g on it’s own (assuming the fat and fibre content in the meals were matched).
Does this mean we should just eat 100g of protein in on sitting then? Probably not, how much we can absorb and how much our body can actually put towards creating new muscle at one time are not the same thing. But that's a topic for another post. Let's just stick with the 3-5 meals per day with adequate protein in each, yeah?
Hope you found these helpful.
References: Timing of protein: https://academic.oup.com/jn/article/139/6/1103/4670442 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5596471/
Dosage: https://academic.oup.com/ajcn/article/89/1/161/4598235 https://physoc.onlinelibrary.wiley.com/doi/abs/10.1113/jphysiol.2012.244897%4010.1002/%28ISSN%291469-445X%28CAT%29VirtualIssues%28VI%29VirtualIssue2016 https://www.ncbi.nlm.nih.gov/pubmed/29497353 https://bjsm.bmj.com/content/52/6/376.long https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5828430/ https://www.ncbi.nlm.nih.gov/pubmed/24257722
Plant protein strategy: https://www.ncbi.nlm.nih.gov/pubmed/26224750
Dosage and age: https://www.physiology.org/doi/abs/10.1152/ajpendo.00488.2005
Protein intake over protein timing: https://www.ncbi.nlm.nih.gov/pubmed/26764320