Most people think they understand their protein needs pretty well—just get as much as you can, right? Or maybe you’re in the camp that thinks “I’m a climber, not a bodybuilder, so I really don’t need much at all. I mean, the forearms are tiny little muscles, right? It doesn’t take much to maintain them…” Either way, I’ve met only a few people who weren’t afraid to admit they didn’t really understand protein and many, many more who had solidly wrong ideas about it.
It’s not their (or your) fault; protein is difficult. The problem is that protein doesn’t really work like the other macronutrients. Whereas fats and carbohydrates are easy(ish) to account for because they provide us with energy through their breakdown, protein for the most part does not. Protein contains calories in the sense that it’ll release four kilocalories of energy when oxidized in a calorimeter (as a gram of gasoline would release 10.5 kilocalories), but day-to-day your body doesn’t run off protein like it runs off fat or carbohydrates. Sure there’s some limited conversion of protein to carbohydrate, providing a trickle of energy, but mostly the body uses protein to build and maintain itself—a process that doesn’t follow the same linear type of equation as “calories in vs. calories out“, and thus becomes difficult to understand.
In the past, we’ve resorted to using our bodyweight as a guide for our protein needs, as in “Aim for 1.4 to 2.0 grams of protein per kilogram of bodyweight if you’re a power athlete.” This “grams per kilogram” model is tried and true for estimating the minimum amount of protein we need to remain healthy (0.8 grams per kilogram, or about your body weight divided by 3 in ounces), but that’s really a different question aimed at a different problem. Today, we have enough information to discard the “grams per kilogram” model for athletes and move to a NEW model for protein.
Let’s learn why.
First, I should begin by saying that the “grams per kilogram” model for protein needs does work—but it works mostly by accident. Different sources quote different figures for how much protein an endurance or power athlete should consume each day, but they usually fall pretty close to a minimum of 1.2 grams per kilogram per day and a maximum of 2.0 grams per kilogram per day. Obviously, this gives quite a range for protein intake depending on your weight and the type of athlete you are, but it’s safe to assume that most athletes using this model will consume at least 100 grams of protein per day and probably closer to 120 grams.
If you eat this much protein, you’re pretty close to what the newer model would call the “ideal amount” of protein—not too high, not too low. In the newer model, though, we really don’t care how much you weigh, or what your sex is, or even what sort of athlete you are because those are all completely irrelevant to the basic metabolism of protein. You could be a twiggy 100 lbs or a bulky 300 lbs and your body is going to digest, absorb, and respond to the protein you feed it in almost the exact same way.
This seems unintuitive, I know, and anecdotal evidence clearly demonstrates that your typical athletic male is more muscular than your typical athletic female—but anecdotes be damned, it’s also the truth! When both the amount of protein and the type of stimulus (e.g., exercise) is controlled, everybody has nearly the exact same physiological response to protein. Apparently, men wind up more muscular than women solely because they have greater baseline levels of testosterone, which makes their bodies more prone to muscle growth over the long-term (this is particularly evident during puberty). But over just the short-term, when we’re looking at some men and women who have just done the same exercise and eaten the same amount of protein, we see no difference in muscle protein synthesis.
Okay, with that brief detour done about why the “grams per kilogram” model is loosely accurate, let’s move onto the new model itself.
The New Protein Model
The new protein model is…
I have a confession: there isn’t really a “new protein model”. If you Google it, you’re not going to find anything. The truth is I made that term up just to pique your interest and no such “new model” really exists—but given what we know from recent research, we should be confident there will be one soon and that it will closely resemble what I’m about to recommend. I’ll explain why that is in a bit, but I think I’ve held you in anticipation long enough.
The “New Protein Model” is this:
No matter your height, weight, or sex, ALL athletes (including climbers) should aim for about 120 grams of protein daily, divided as evenly as possible into 20 gram servings that are themselves separated by around three hours.
Okay, there it is in all it’s simple glory. It doesn’t matter if you’re male or female, skinny or brawny, or whether you climb, bike, swim, or pump iron. All of you can (and will) benefit from the exact same amount of protein, divided up into the same six “meals” separated by three hours. Or, to put it another way, you’re probably getting enough protein everyday—but you’re probably not getting it at the right times. With the new model, you’re going to shift your protein intake around so that you never have big gaps and you don’t pig out on protein just a couple times a day.
You’ll start your day with a protein-rich breakfast, you’ll have a protein-rich snack sometime mid-morning, and you’ll have a protein-rich lunch. In the afternoon you’ll enjoy another protein-rich snack, then you’ll eat a protein-rich dinner, and right before you go to sleep you’ll have one last protein-rich snack. In all these cases, “protein-rich” means about 20 grams of protein, which is probably a lot less than you normally get during lunch or dinner and a lot more than you get during the rest of your meals and snacks.
Easy, right? Maybe too easy? Maybe you don’t believe me. Fine, then let’s move on to the science where I can demonstrate why this is correct.
Maximize That Muscle Protein Synthesis!
The first question you probably have is, “Where the hell did you grab that 20 gram figure from?” It seems random, but it’s not—it’s based on several studies, all of which show that muscle protein synthesis plateaus when protein intake reaches 20 grams.
We have, for example, this study that showed how 20 grams of whey protein elicited virtually the exact same increase in muscle protein synthesis as 40 grams (49% vs 56% increases, respectively). Or we have this study that showed how muscle protein synthesis was almost exactly the same whether 20 grams or 40 grams of egg protein was consumed. Or this study that found eating 12 oz of lean ground beef (90 grams of protein) resulted in equivalent muscle protein synthesis as only 4 oz (30 grams of protein). Actually, in the last study the larger serving of ground beef resulted in lower muscle protein synthesis, though it was statistically insignificant.
These are three very different proteins given to mixed groups of people (young, elderly, male, female, resistance-trained, non-resistance-trained) and yet every study shows virtually the same thing: it only takes 20 grams of protein to maximally stimulate muscle protein synthesis. The only catch is that all three proteins were high-quality proteins, meaning rich in essential amino acids—but that’s not a problem for you, right? Even vegans can opt for higher- over lower-quality proteins in their meals, they just have less variety to choose from.
(We’ll cover this idea of protein quality in another article; right now, it’s only important to know that most high-quality protein sources are exactly what you already think they are: meat, fish, dairy, eggs, soy, and rice and pea proteins.)
So that’s where my 20 gram figure came from—the numerous studies that all have come to roughly the same conclusion about how much protein is necessary to “get the most” out of your muscles. On the flipside, the two studies that also looked at 10 gram doses of protein found that they were significantly worse at boosting muscle protein synthesis, so the curve rises steeply until around 20 grams and then levels out (it’s logarithmic for you math geeks out there). Thus, 20 grams is the magic number: enough to boost muscle protein synthesis to 90% or more of it’s maximum but not so much that we just waste the protein.
Okay, but what about the “every three hours” part? To answer this, we need to look at another study and then take the logic a few steps further based on what we learned from the above studies. The goal of this other study I just mentioned was to measure how the timing of the same amount of protein affects total muscle protein synthesis. To this effect, they fed all the study participants 80 grams total of whey protein and just changed when they got it and in what sub-amounts. Observe:
- Group 1 had eight total doses of 10 grams of protein split up by 1.5-hour chunks
- Group 2 had four total doses of 20 grams of protein split up by 3-hour chunks.
- Group 3 had two total doses of 40 grams of protein split up by 6-hour chunks.
The results probably shouldn’t come as a shock to you, but Group 2 had significantly more muscle protein synthesis (when averaged across all 12 hours) than either Group 1 or Group 3. By itself, this is already a strong indicator that the “20 every 3” rule is solid, but for the sake of thoroughness let’s take it a step further.
One issue you bring up about the above study is that whey is a notoriously “fast” protein; in terms of the speed it can be digested and absorbed, it has few rivals. Whey is, in fact, often considered a king among proteins for this exact reason, because it is so quickly absorbed into our body—but the shadow of this monarch is that the amino acids it so rapidly releases also leave quickly. They flit into our blood so easy, but in just a few hours they’re gone. Slower-digesting proteins, on the other hand, sustain higher levels of blood amino acids for longer periods of time. With this in mind, you might wonder if that’s one reason why Group 2 fared so much better than Group 3—the quick speed at which whey is digested would surely favor a more frequent feeding window than a slower protein, which would itself benefit from longer gaps between feedings.
It seems like a solid hypothesis, but let’s consider what we’ve learned from the other studies. Of the three studies mentioned above, two used “slower” proteins: egg and beef. In the egg and the beef trials, a larger dose of protein still failed to boost muscle protein synthesis to a greater degree than just 20 grams, even when measured across four hours (egg) or five hours (beef). If a slower protein was more adept at boosting muscle protein synthesis long term, then we would see boosts for these slow proteins across such a long timespan as four or five hours. We don’t, though; instead, all the extra amino acids released from the extra large doses of protein were just oxidized into energy or converted to nitrogen waste. For all those extra 20 grams of “slow protein” were worth, they may as well not have even been consumed.
Combining everything we’ve learned from the above studies, we can thus say with reasonable certainty that…
- There’s no reason to consume more than about 20 grams of high-quality protein in any given meal.
- Meals are best separated by about three hours.
…and this brings us to that special figure of 120 grams, because unless you’re waking up in the middle of the night to have a snack (or sleep less than 6 hours), you only have time for six meals divided by three hours. (e.g., 7:00AM, 10:00AM, 1:00PM, 4:00PM, 7:00PM, 10:00PM—six meals in 15 hours).
Part I Recap
So that’s the “new model” for protein. It’s tremendously simple, not very personal, and probably the easiest bit of sports nutrition you’ll ever have to worry about (though it’s still ridiculously hard to really wrap your head around why it works that way).
120 grams of protein per day, divided into six meals of 20 grams, separated by three hours.
There are caveats and nitpicky details to be sure, but this very basic statement is all you really need to know in order to maximize the potential of the protein in your diet. In the next couple parts, I’ll go over the caveats and nitpicky details just so you can see the rest of the logic in this recommendation—but if you decide to stop here (and you follow this advice) you’re going to be fine.