One of many key articles of religion of recent sports activities diet is that your physique can solely use a specific amount of protein at a time. Opinions differ on what that quantity is. It is perhaps as little as 20 grams; it is perhaps as a lot as 40 grams, notably for older adults whose our bodies are much less delicate to the muscle-growth-stimulating results of protein. Possibly it must be expressed relative to physique dimension, like 0.4 grams per kilogram of physique weight, quite than as a hard and fast quantity. These particulars don’t matter right here; the purpose is that there’s a most.
The rationale that’s necessary is that almost all North People eat numerous protein, however don’t unfold it evenly all through the day. A typical sample is perhaps 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 recent 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, based on this logic, is to clean out your protein consumption so that you simply’re getting a minimum of 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 maybe even one other one proper earlier than mattress.
That’s the standard knowledge. So a latest research in Cell Stories Drugs 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 beforehand), has generated loads of buzz. Briefly, van Loon’s new information suggests there’s no higher restrict on protein in spite of everything, and that massive doses of protein—they use 100 grams within the research, as a result of that’s about how a lot protein they figured they may eat at a barbecue with out force-feeding themselves—produce proportionately bigger will increase within the formation of recent muscle.
A Distinctive Sort of Protein Examine
The research concerned 36 volunteers cut 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 completely different chemical kind than standard, enabling the researchers to trace the progress of the protein drink because it was digested and integrated into new muscle proteins within the topics’ our bodies. (I as soon as interviewed certainly one of van Loon’s postdocs about an earlier “glowing cow” experiment, and he described the sudden obligations he needed to tackle: “My job was to speak to them, brush them, and mainly preserve 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 mainly concerned sitting round for 12 hours and taking a bunch of blood samples and muscle biopsies to determine what was taking place within the topics’ muscular tissues following the exercise-protein combo. That mixture is necessary: each resistance train and consuming protein increase the formation of recent muscle protein, however placing them collectively inside a window of 4 to 6 hours produces a muscle-building impact that’s higher than the sum of its elements. The total suite of measurements and evaluation is extraordinarily complicated (and free to examine, for those who’re ), however crucial parameter is how a lot new muscle protein is being synthesized, as a result of that’s what (kind of) dictates how a lot muscle you’ll achieve over time.
There are two key issues in regards to the research. One is the time-frame: most earlier research solely monitored muscle protein synthesis for six hours or much less, so 12 hours supplies a for much longer window for the consequences of a giant protein dose to indicate up. The second is the protein dose: earlier research topped out at 45 grams, so it might have been laborious to see massive variations in comparison with, say, 20 or 30 grams.
Right here’s the important thing consequence, displaying 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 straight away. And the most important 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 instances extra protein doesn’t offer you 4 instances the synthesis—nevertheless 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—a minimum of, one at 40 grams or much less—was fallacious. You all the time need to be cautious about chucking away a complete bunch of seemingly settled science on the premise of a single research. However this research 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 appropriate. 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 person 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 have to time your exercise round your 100-gram protein bomb. If I carry weights within the morning then get all my protein within the night, or vice-versa, does that also work?
There are definitely people who find themselves into the one-meal-a-day factor, and for these individuals this is a crucial consequence. Of their dialogue, van Loon and his colleagues notice that their findings recommend that time-restricted feeding shouldn’t essentially result in muscle loss. For me, the principle takeaway is that it’s most likely not as necessary as I as soon as thought to unfold my protein completely all through the day. That gained’t change how I truly eat, as a result of getting 25 grams of protein at each single meal has all the time been extra aspiration than actuality—however a minimum of I’ll really feel much less responsible about it.
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