For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use.
29 likes 15mo
Topic summary
DXA precision and the least significant change for lean mass — the long version
This is a generated summary. It shows the 9 most-liked posts from a topic of 112, 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.
Coming back to post #29, because the follow-up matters more than the original answer.
Resting metabolic rate: body composition affects metabolic rate. As fat mass decreases and lean mass is maintained, metabolic rate is usually maintained better than with simple weight loss alone.
30 likes 15mo
Picking up post #42: that is the part I would want checked first.
Maintenance phase: tracking body composition during maintenance (weight stable) is different from tracking during active loss. Changes are smaller and precision becomes more important.
28 likes 14mo
unit_conversion, post #21: Lean mass loss during rapid weight reduction: depends on protein intake, resistance training volume, and total energy deficit. Adequate protein and maintaining training intensity both help preserve lean mass. Go to post
I read post #51 twice before replying, because I had assumed the opposite.
Changes during titration: measuring body composition during active titration is less useful than measuring after dose is stable. Titration causes fluid shifts that confound body composition.
On post #58 — agreed on the reasoning, with one qualification.
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.
30 likes 14mo
post #73 is right about the mechanism and I think understates the practical bit.
Changes during titration: measuring body composition during active titration is less useful than measuring after dose is stable. Titration causes fluid shifts that confound body composition.
28 likes 14mo
p.fontaine, post #38: post #37 is right about the mechanism and I think understates the practical bit. Bioelectric impedance analysis: less precise than DXA and strongly affected by hydration state. Not reliable for detecting month-to-month changes. Useful for trend over years if done consistently. Go to post
post #86 is right about the mechanism and I think understates the practical bit.
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.
a.hartmann, post #49: For anyone arriving from a search: the marked solution above is the direct answer, and the replies underneath it add the caveats that make it safe to use. Go to post
Changes during titration: measuring body composition during active titration is less useful than measuring after dose is stable. Titration causes fluid shifts that confound body composition.
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- Interpreting a composition change that is within the error barsOutcomes › Body composition · 22 replies
Moved from Progress reports by s.leclerc. Category placement is not obvious from outside and getting it wrong is expected. This topic will get better answers here. The move is recorded in the public log citing R7.
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