On DXA precision I would separate what is worth knowing from what is worth acting on. The first list is long and the second is short, and conflating them is how threads get heated.
26 likes 8mo
Topic summary
DXA precision and the least significant change for lean mass
This is a generated summary. It shows the 9 most-liked posts from a topic of 86, in their original order, with the accepted answer included where one exists. It is a reading aid and it will miss nuance — the full topic is the record.
DXA (dual-energy X-ray absorptiometry): the standard for body composition in research. Precision is roughly ±1 kg for lean mass. Two scans six months apart on the same machine with the same technician give you useful information. Two scans six weeks apart on different machines tell you about the machines.
That has been true for the cases I have seen and I have not seen many.
25 likes 8mo
The most useful reply I ever got about DXA precision was a request to state my units. It sounds like pedantry and it has saved me twice.
25 likes 8mo
Coming back to post #53, because the follow-up matters more than the original answer.
DXA on the same machine with the same technician has a least significant change for lean mass of roughly a kilogram, sometimes more. Below that, two scans are the same scan.
The conclusion is tentative; the arithmetic underneath it is not.
33 likes 8mo
Coming back to post #64, because the follow-up matters more than the original answer.
Preserving lean tissue during a substantial deficit depends on protein intake and a resistance stimulus, and the evidence for both is reasonably strong.
Posting it because the silence on this was starting to look like agreement.
30 likes 7mo
b.adeyemi, post #76: Following, with nothing to contribute beyond having asked the same thing elsewhere. Go to post
Comparison to published data: the trials reported mean fat and lean mass changes. Individual results vary around that mean. Being above or below average is not a sign of something wrong.
The disagreement above is smaller than it looks once the terms are fixed.
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