Short answer first, then the reasoning. 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.
I lifted three times a week throughout and still lost lean mass. Not as much as I expected to, but the idea that training prevents it entirely is not what my scan says.
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 actually want to know is whether resistance training and protein change the ratio or only the absolute amount.
Not looking for reassurance. Looking for the part I have got wrong.
Dr.SportsMedIN said:There is also a quality change that the scan cannot see.
Right, and 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.
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Shop Reference StandardsMarkLI_maint said:I lifted three times a week throughout and still lost lean mass.
Can confirm the pattern MarkLI_maint describes. 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.
Adding the clinical framing, because it changes how the question reads.
DEXA scan update relevant to lean mass:
Scanned at months 0, 6, and 12. Here are the body comp numbers:
| Baseline | Month 6 | Month 12 | |
|---|---|---|---|
| Total mass | 251 lbs | 221 lbs | 198 lbs |
| Fat mass | 101 lbs | 71 lbs | 48 lbs |
| Lean mass | 154 lbs | 150 lbs | 155 lbs |
| Body fat % | 44% | 30% | 22% |
Lean mass preserved — actually GAINED 1-2 lbs thanks to progressive overload + 1.4g/kg protein. The lean mass discussion needs to include body comp data, not just scale weight.