The internet says one gram of protein per pound of bodyweight. You weigh 150, so 150 grams a day, done thinking. It is a fine starting point. It is also wrong for a lot of women who train, and wrong in a direction that costs you muscle.
That rule was built for an average gym-goer, somewhere between losing and maintaining, training a few times a week, average in body composition. If you train hard for strength and are trying to keep muscle while you lean out, it can run low. If you carry more body fat, using total bodyweight can run high. And it never once asks how you actually train, which is the thing that should move the number most.
Why “one gram per pound” is oversimplified
The rule is easy to remember, roughly right for a big slice of people, and it errs toward “more is fine,” because extra protein mostly just costs money. But it ignores two things that matter.
First, it uses total bodyweight instead of lean body mass. A woman at 150 pounds and 22% body fat carries about 117 pounds of lean tissue. The same weight at 32% is about 102 pounds of lean tissue. The leaner one needs more dietary protein to maintain that muscle. The rule treats them the same.
Second, it ignores how you train. Someone doing heavy strength work and someone doing mostly easy cardio at the same weight have different protein demands. The training is the signal, and the shortcut throws it away.
How your training should shift your protein target
A 2018 meta-analysis in the British Journal of Sports Medicine (Morton et al.) found that protein past roughly 1.6 grams per kilogram of bodyweight gave diminishing returns for strength and muscle in trained people. That is the well-lit ceiling. The floor and the middle depend on what you do.
Rough guide, in grams per pound of bodyweight:
- Strength-focused, keeping or building muscle: 0.8 to 1.0, biased high when eating in a deficit.
- A mix of strength and conditioning: 0.7 to 0.9.
- Mostly cardio with some strength work: 0.6 to 0.8.
- Leaning out: everyone edges toward the top of their range, because a deficit with low protein is how you end up smaller and weaker instead of stronger.
These are not revolutionary numbers. They are just less blunt than one gram per pound.
Muscle matters more than the number on the scale
Two women at the same weight can carry very different amounts of muscle. The one with more needs more dietary protein to hold it. Most apps do not ask about this, because estimating body composition is awkward, so they round to bodyweight and hand you a number that can be off by a fifth for anyone who is not average.
What TrakMac does differently
TrakMac asks questions you actually know the answer to, about how you train and what you can do, not just your height and weight. Those answers are signals. How you train says more about your protein and calorie needs than your birthday does. The app maps those signals onto your body composition and training, then sets your protein target to match, instead of a generic formula wearing a progress bar.
How to find your real target by hand
If you do not have an app doing the math:
- Estimate your body fat honestly.
- Lean body mass is bodyweight times (1 minus your body fat percentage).
- Multiply lean body mass by 1.0 to 1.2 grams per pound. That is your daily protein floor.
- Keeping muscle while leaning out, stay high. Maintaining, the middle is fine.
That gets you closer than one gram per pound for any body that is not average.
Download TrakMac
TrakMac sets your protein target from how you actually train, not just your weight. Download TrakMac free. iOS, available now. More on how the setup questions feed the math is in the FAQ.