Ask ten lifters how much protein to eat and you will get ten numbers, four of them delivered with the serene confidence of a man who has never read a study and does not intend to start now. The number itself is not actually controversial. What people are arguing about, mostly, is each other.
So: roughly 1.6 to 2.2 grams per kilogram of body weight per day, if you train with weights and want to build or keep muscle. The literature has been orbiting that band for twenty years, and the meta-analyses keep landing in the same neighbourhood no matter how the authors feel about each other at conferences. For an 80 kg lifter that is about 130 to 175 grams a day. In pounds, if you must, call it 0.7 to 1.0 g per pound and stop doing the conversion in the supermarket like a man solving a riddle.
That is the answer. The rest of this is about why it is a range, and about the considerably more humiliating problem sitting underneath it.
Why it is a range and not a number
Three reasons, none of them mysterious.
Deficit or surplus. Eating below maintenance is the situation where protein earns its reputation. Your body is looking for tissue to break down and it does not have strong opinions about which tissue. More protein (the upper half of that band, comfortably) plus training that gives the muscle a reason to stay is the standard defence. In a surplus you can sit at the lower end and spend the calories elsewhere.
Training age. Somebody eight weeks into lifting will build muscle on almost any reasonable intake, because everything works when nothing has been tried yet. Somebody eight years in is fighting for grams, and the margins that were rounding errors in year one are the whole game.
How you count body weight. At very high body-fat percentages, scaling protein to total scale weight overshoots; lean mass is what needs feeding. This matters for a minority of readers and gets cited by a great many more, generally the ones looking for a reason not to eat their chicken.
The thing nobody puts in the headline
Here is the part that decides outcomes, and it is not a number.
Most people do not know what they eat. Not roughly. Not within twenty grams. Ask someone confident to estimate a day's protein and then have them weigh it, and the gap is routinely enormous in the direction you would expect, because a chicken breast is 150 g when you are eating it and 250 g when you are describing it.
Which is why the argument about 1.6 versus 2.0 is largely theatre. If your intake swings between 90 g and 190 g depending on whether Tuesday went well, the target is decorative. You are not undershooting the optimum. You are not measuring at all.
The fix is dull and it works: log for two or three weeks without changing anything. Not to hit a number. To find out what your number currently is. Almost everyone is surprised, and almost nobody is surprised upward.
Timing, which matters less than the internet thinks
The anabolic window turned out to be a barn door. Total daily intake dominates; distribution is a second-order effect. Three to five protein-containing meals is a fine default, there is modest evidence it beats one heroic serving at 9 p.m., and if you have been losing sleep over whether your post-workout shake landed within forty minutes, you have been optimising the wrong end of the problem by roughly an order of magnitude.
Get the daily total right for a month. Then, if you are still bored, worry about timing.
Where the training log comes in
Protein intake is not an outcome. It is an input, and inputs are only interesting next to what they produced.
The question worth asking is not "did I hit 160 g" but "over twelve weeks, at this intake and this calorie balance, did my lifts go up and my weight do what I asked of it?" That comparison needs food and training on the same timeline, which is the argument for keeping them in one app and not in two apps that have never met.
A stalled bench at 130 g in a deficit and a stalled bench at 130 g at maintenance are different diagnoses with different prescriptions. Neither app knows that alone.
Doing it in OneRep
Set a protein target and it sits on the day's ring alongside calories. Barcode-scan the packaged stuff, photo-log the plate of leftovers you were never going to weigh, since each is faster in different situations, and let the daily total accumulate without ceremony.
Then look at it as a twelve-week line rather than a Tuesday, beside your body weight and your working sets. Ask Coach why the numbers look the way they do; it can see all three, which puts it ahead of most of the people who will offer you an opinion.
Try it: Free, no trial window.
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