You’d have a tough time discovering any critical endurance athlete in 2025 who thinks protein doesn’t matter. Gone are the carb-centric days of pasta and Gatorade and nothing else. However determining how a lot protein runners, cyclists, and different endurance junkies really want—and once they want it—stays a piece in progress.
I’ve grappled with these questions just a few instances not too long ago—in a chunk busting some frequent protein myths, and in one other discussing the thought of most protein consumption. However now a new assessment paper in Sports activities Medication, from a analysis crew led by Oliver Witard of King’s School London, affords a complete overview of the present state of information. Witard and his colleagues give attention to two key questions. First, how a lot protein do endurance athletes want every day to remain wholesome and optimize long-term coaching variations? And second, what position can the tactical use of protein play in rushing up short-term restoration and boosting efficiency?
Protein for the Lengthy Time period
Authorities tips at the moment suggest getting at the least 0.8 grams of protein per kilogram of physique weight (g/kg) every day. For somebody who weighs 150 kilos, that works out to 55 grams of protein. For reference, a regular 5-ounce can of tuna has about 20 grams of protein.
There are two essential issues with this guideline, nonetheless. First, it’s meant to be the minimal required to remain wholesome, not the optimum quantity to maximise efficiency. Second, it was formulated utilizing a measurement method that entails monitoring the quantity of nitrogen being consumed and excreted from the physique, which some scientists consider underestimates protein wants. A more moderen method referred to as the “indicator amino acid oxidation methodology,” which entails labeling one particular kind of amino acid with a carbon isotope to see how shortly it’s burned, offers greater numbers and can also be extra sensible for testing particular populations like athletes.
The standard argument for getting a lot of protein is that it offers the constructing blocks—amino acids—for constructing new muscle. That’s necessary for energy coaching, however endurance athletes want it for different causes. One is that these constructing blocks are used to restore the muscle injury incurred by arduous coaching: the longer and tougher you run, the extra injury you incur, and extra protein you presumably want for repairs.
Throughout extended train, your physique additionally begins burning amino acids for gasoline. The quantities are usually small, and the way a lot you burn is determined by the character of the train and what else you’re consuming, however in some instances 5 to 10 p.c of the gasoline you want for a given exercise is offered by protein. In case you’re coaching arduous, you’ll have to eat further protein to interchange these losses.
There are some extra refined prospects, too. Muscle isn’t the one a part of the physique that’s constructed from protein. One of many key variations athletes acquire from endurance coaching is a rise within the quantity of protein within the mitochondria, the place mobile power is generated. The extra protein within the mitochondria, the extra effectively it creates power. A number of research have sought to determine whether or not consuming extra protein boosts the mitochondrial response to train. The outcomes to date haven’t been convincing, but it surely’s nonetheless an open query.
Witard and his colleagues pooled information from numerous indicator amino acid research to evaluate protein wants for endurance athletes below numerous situations. Listed here are among the key numbers:
The indicator amino acid information means that even untrained folks want about 1.2 g/kg of protein per day, 50 p.c greater than the FDA’s advisable every day consumption of 0.8 g/kg. And endurance athletes want one other 50 p.c greater than untrained folks, with a stage of 1.8 g/okay/g guaranteeing that 95 p.c of persons are getting all of the protein their our bodies can use. As compared, research utilizing the identical indicator amino acid methodology discover that resistance-trained athletes want someplace between 1.5 and a couple of.0 g/kg per day, elevating the chance that endurance athletes may really want extra protein than lifters.
There’s an necessary level to remember, although: endurance athletes additionally are inclined to eat much more than the common particular person, which suggests they mechanically get extra protein. Present protein consumption amongst American adults averages 1.25 g/kg for males and 1.09 g/kg for ladies, fairly near the general goal of 1.2 g/kg for untrained folks. As compared, one research discovered that endurance athletes common 1.4 to 1.5 g/kg—not fairly on the 1.8 g/kg stage, however not that far-off.
There are another nuances in that graph. Knowledge on male-female variations could be very sparse, however there are some hints that girls may require greater than males relative to their physique weight. That may be significantly true through the luteal section of the menstrual cycle, since progesterone can have an effect on protein burning. Witard and his colleagues make a blanket suggestion that each female and male endurance athletes ought to purpose for 1.8 g/kg, however they throw within the speculative chance that females “could take into account” upping it to 1.9 g/kg through the luteal section of their cycle.
Quick-Time period Protein Techniques
The massive shock within the information above is that endurance athletes appear to make use of extra protein on their relaxation days than on coaching days. This discovering has popped up in just a few research, and it’s positively not what the scientists had been anticipating. It’s potential that there’s some quirk of metabolism that’s skewing the measurements used to evaluate protein wants whenever you attempt to evaluate train and non-exercise days.
But it surely’s additionally potential that the impact is actual—that whenever you give your physique a break, its restore and adaptation mechanisms kick into overdrive and thus use extra protein than ordinary. If that is true, it’s an argument for upping your protein consumption on relaxation days: Witard and co. counsel aiming for two.0 g/kg. And on a extra elementary stage, it’s an argument for together with true relaxation days in your coaching program periodically, since they appear to set off restoration processes that don’t occur on regular coaching days. At this level, I’d say the jury remains to be out on whether or not the impact is actual.
Both approach, the researchers counsel aiming for 0.5 g/kg of protein following train to assist restore any muscle injury incurred through the exercise. For a 150-pound particular person, that’s 34 grams of protein, which is what you’d get in a considerable meal with a very good protein supply. How quickly is “after train”? I don’t suppose there’s any convincing information that claims it must be instantly after. Your subsequent meal is okay—until your exercise was after dinner and also you’re planning to go to mattress, by which case it is best to make a particular effort to get some protein in.
The information additionally means that athletes use extra protein once they’re coaching in a carbohydrate-depleted state. On this case, we’re not speaking a few persistently low-carb food regimen, however reasonably doing sure coaching periods in a low-carb state to assist the physique adapt to burning fats extra effectively. There’s first rate proof that protein can assist energy these exercises, and Witard suggests taking in 10 to twenty grams of protein earlier than and/or throughout such a session.
This concept of utilizing protein to compensate for low carbs additionally connects to one of the hotly debated concepts about protein for endurance athletes. There have been numerous research-backed claims through the years that including protein to a sports activities drink that you simply eat throughout a race or coaching session will improve your efficiency, and that taking in some protein within the quick post-workout window will pace up the speed at which you refill the carbohydrate shops in your muscle tissues.
All these claims, Witard and his colleagues argue, are the results of research the place the topics didn’t get sufficient carbohydrates. In case you’re assembly your carb wants, including protein to a sports activities drink will neither enhance your efficiency nor speed up your muscle refueling. There could also be exceptions for ultra-endurance occasions, which haven’t been well-studied and have considerably completely different metabolic challenges in comparison with a marathon. However the researchers’ remaining conclusion is a reminder that for endurance athletes, regardless of protein’s present recognition, carbohydrate remains to be king.
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