One of many key articles of religion of recent sports activities vitamin is that your physique can solely use a certain quantity of protein at a time. Opinions differ on what that quantity is. It could be as little as 20 grams; it could be as a lot as 40 grams, significantly for older adults whose our bodies are much less delicate to the muscle-growth-stimulating results of protein. Perhaps it must be expressed relative to physique dimension, like 0.4 grams per kilogram of physique weight, moderately than as a set quantity. These particulars don’t matter right here; the purpose is that there’s a most.
The explanation that’s necessary is that almost all North Individuals eat a lot of protein, however don’t unfold it evenly all through the day. A typical sample could be 10 to fifteen grams at breakfast and lunch, then 65 grams or extra at dinner. That signifies that at breakfast and lunch, you’re not getting sufficient protein to max out the synthesis of latest muscle protein. At dinner, then again, you’re getting an excessive amount of, so the surplus will merely be burned for power. The higher answer, in accordance with this logic, is to clean out your protein consumption so that you simply’re getting at the very least 20 grams (or 40 or 0.4 grams per kilogram or no matter) at every meal, including a protein-rich snack someday in the course of the day, and even perhaps one other one proper earlier than mattress.
That’s the traditional knowledge. So a recent study in Cell Reports Medicine from researchers at Maastricht College within the Netherlands, led by famous muscle physiologist Luc van Loon (whose vivid, no-nonsense recommendation I’ve written about previously), has generated loads of buzz. In brief, van Loon’s new information suggests there’s no higher restrict on protein in any case, and that massive doses of protein—they use 100 grams within the examine, as a result of that’s about how a lot protein they figured they might eat at a barbecue with out force-feeding themselves—produce proportionately bigger will increase within the formation of latest muscle.
A Distinctive Sort of Protein Examine
The examine concerned 36 volunteers break up into three teams. They every did a one-hour weight-training exercise after which instantly downed a drink containing both 0, 25, or 100 grams of protein. The protein got here from the milk of a Holstein cow that the researchers injected with a particular carbon isotope tracer. This meant that one of many amino acids within the milk had a barely totally different chemical kind than traditional, enabling the researchers to trace the progress of the protein drink because it was digested and included into new muscle proteins within the topics’ our bodies. (I as soon as interviewed considered one of van Loon’s postdocs about an earlier “glowing cow” experiment, and he described the surprising tasks he needed to tackle: “My job was to speak to them, brush them, and principally maintain them in temper,” he recalled. “If the animal turns into pressured, milk manufacturing declines, so we handled them like princesses.”)
Anyway, the following a part of the experiment principally concerned sitting round for 12 hours and taking a bunch of blood samples and muscle biopsies to determine what was occurring within the topics’ muscle tissue following the exercise-protein combo. That mixture is necessary: each resistance train and consuming protein enhance the formation of latest muscle protein, however placing them collectively inside a window of 4 to 6 hours produces a muscle-building impact that’s larger than the sum of its components. The total suite of measurements and evaluation is extraordinarily advanced (and free to read about, should you’re ), however an important parameter is how a lot new muscle protein is being synthesized, as a result of that’s what (roughly) dictates how a lot muscle you’ll acquire over time.
There are two key issues in regards to the examine. One is the timeframe: most earlier research solely monitored muscle protein synthesis for six hours or much less, so 12 hours gives a for much longer window for the results of a giant protein dose to point out up. The second is the protein dose: earlier research topped out at 45 grams, so it might have been exhausting to see large variations in comparison with, say, 20 or 30 grams.
Right here’s the important thing end result, exhibiting protein synthesis over the 12 hours following the exercise and protein drink. Black circles are the 100-gram group; gray circles are the 25-gram group; and white circles are the 0-gram management group:
The impact isn’t delicate: the 100-gram group is getting far more protein synthesis than the 25-gram group instantly. And the largest distinction comes after the six-hour (i.e. 360-minute) mark: by that time, the 25-gram group is again to baseline, whereas the 100-gram group nonetheless hasn’t gone again to baseline even after 12 hours. The additional protein synthesis isn’t precisely proportional—that’s, 4 occasions extra protein doesn’t provide you with 4 occasions the synthesis—however it’s substantial.
What the New Protein Findings Imply for Athletes
There’s an easy conclusion right here, which is that the thought of a most protein dose—at the very least, one at 40 grams or much less—was unsuitable. You all the time wish to be cautious about chucking away a complete bunch of seemingly settled science on the idea of a single examine. However this examine appears strong, and it has recognized some clear gaps—in period and protein dose—within the earlier research that it’s overturning. So let’s assume for now that it’s right. The query, then, is what it means for the way athletes ought to eat.
For sensible functions, the true apples-to-apples comparability would have been 100 grams of protein versus 4 doses of 25 grams spaced 4 hours aside. Which sample would produce extra protein synthesis in that comparability? No one is aware of at this level. There are a bunch of different causes that I’ll be sticking with three meals a day, together with the truth that I actually take pleasure in all my meals. As an endurance athlete, I’m additionally as aware of my carbohydrate provide as I’m of protein. And even for protein and muscle-building, there are many unanswered questions—like whether or not you’d must time your exercise round your 100-gram protein bomb. If I raise weights within the morning then get all my protein within the night, or vice-versa, does that also work?
There are actually people who find themselves into the one-meal-a-day factor, and for these individuals this is a vital end result. Of their dialogue, van Loon and his colleagues observe that their findings counsel that time-restricted feeding shouldn’t essentially result in muscle loss. For me, the primary takeaway is that it’s in all probability not as necessary as I as soon as thought to unfold my protein completely all through the day. That gained’t change how I really eat, as a result of getting 25 grams of protein at each single meal has all the time been extra aspiration than actuality—however at the very least I’ll really feel much less responsible about it.
For extra Sweat Science, be a part of me on Threads and Facebook, join the email newsletter, and take a look at my ebook Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance.
