A reference post rather than a discussion. Corrections are the point; I would rather this be right than mine. It is about lean-mass preservation, and it is deliberately narrow — everything I am not confident about is marked as such.
What is actually established
There is also a quality change that the scan cannot see. Weight loss shifts fiber-type distribution toward Type I and improves mitochondrial density and insulin-stimulated glucose uptake per fiber — so the muscle you keep is metabolically better even though there is less of it. That does not make the loss irrelevant, but it explains why function often holds up better than the number suggests.
The condition it depends on
Protein targets should be set on a reference weight rather than current weight. Setting 1.6 g/kg on a starting weight of 130kg produces a target nobody hits on a suppressed appetite.
The practical version
If you are tracking this properly: same scanner, same time of day, same hydration, at least six months apart, and read grip strength or a lift number alongside it. Function is the outcome; the scan is the proxy.
What I am not sure about
So the question, as narrowly as I can put it: whether resistance training and protein change the ratio or only the absolute amount. Numbers rather than impressions, if you have them.
— steph_laguna · corrections welcome and will be edited into this post with credit