This one has a reasonably settled answer, so here it is. 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.
Two DEXA scans eleven months apart: down 24kg total, of which the scan says 6kg was lean. I want to know whether that ratio is bad, normal, or simply what happens.
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.
The narrow version of the question is whether resistance training and protein change the ratio or only the absolute amount.
Happy to be told the question itself is wrong.
JessicaH_TX said:There is also a quality change that the scan cannot see.
Agreed on the ranges, with the condition that a single DEXA is not a measurement, it is one draw from a distribution. Hydration status moves the lean compartment by a kilogram or more between scans, so any comparison of scans done at different times of day or different hydration states is noise.
Happy to go further on any of that.
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Shop Reference StandardsRunnerRach said:Two DEXA scans eleven months apart: down 24kg total, of which the scan says 6kg was lean.
This matches mine closely enough to be worth saying so. The intervention that works is boring and well evidenced: resistance training two to three times a week at a genuine effort, protein at 1.4 to 2.0 g/kg of reference body weight, and not making the deficit larger than the training can support. Cardio does not protect lean mass and in a deep deficit competes with recovery.
From the other side of the consultation, briefly.
OMG yes. lean mass + resistance training is the combo. Can confirm.