Protein Dose Response - New Insights

Alan's Perspective.

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I thought you might be interested in this. A new study from Luc van Loon's lab has given a one-off dose of milk protein at a dose of 0g, 35g or 100g protein. They measured the response over 12 hrs (most studies only measure out to a maximum of 4 hrs). They showed that the dose response isn't what we thought it was. 100g protein was far superior to 25g. We don't normally see that in studies because the protein from such a high dose is still being digested & absorbed when the researchers stop taking measurements.

The implication is not for athletes to see this and think that they need to eat more protein.  Rather the distribution of protein into small 20-40g serves consumed several times a day isn't actually necessary to maximise muscle protein synthesis. This is because a large hit of protein (e.g. from a big steak or chicken breast) will be slowly digested and released across the day/night. For me it simply says that it doesn't really matter whether you distribute protein evenly over the day or not. The gut will do that for you. So, do whatever you prefer in terms of appetite/satiety and food/meal preferences so long as the total protein intake across the day is the same.

Scott's Perspective.

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This study is interesting because it challenges the notion of humans response to maximal dose of protein for muscle protein synthesis. The study involved a milk protein concentrate and enriched it with higher or lower amounts of amino acids with a view to maintain steady state amino acids in the plasma. The reason for this is the assessment of plasma amino acids is a way of measuring protein digestion, absorption and total protein availability. This source of protein (whey concentrate) is going to potentially result in a different response compared to a whole food source. The response to a large amount of protein from chicken, beef, tofu etc would be really interesting to see if the study was repeated. Hopefully it is.  

Another important point to note is that this study was performed on 36 healthy, recreationally trained, male subjects aged 18-40 years of age. It was also performed after a single bout of weight training. We do not know if the results are applicable to older subjects and/or females of similar age or older. More research is required.

In the end, this study opens the possibility for athletes consuming larger volumes of protein in one sitting and still having a similar response to athletes spacing out their protein throughout the day. My main thought. isthat this is cool although eating a huge amount of protein is not always practical due to fullness and timing of training. Spacing out your meals and thus your protein may be more out of necessity rather than any scientific rationale.The other key element to remember is that your total protein intake across the entire 24 hours, week and month is going to have the biggest impact. So, whetehr you eat a large amount of protein early on or not, you still need to hit your total amount of protein for the entire day. If you are a heavier athlete, consuming 2-3g/kg/bodyweight in one hit is pretty bloody hard. Food for thought I think.

REFERENCE:

https://www.cell.com/cell-reports-medicine/fulltext/S2666-3791(23)00540-2
https://twitter.com/JornTrommelen/status/1737186614747500647