Dr.ObesityLA said:DEXA scan update relevant to lean mass: Scanned at months 0, 6, and 12.
Muscle fiber type changes during GLP-1-mediated weight loss, relevant to lean mass: preliminary biopsy data suggests that weight loss shifts the skeletal muscle fiber type distribution:
- Decreased Type IIx (glycolytic, fast-twitch) fibers
- Increased Type I (oxidative, slow-twitch) fibers
- Improved mitochondrial density and function
- Enhanced insulin-stimulated glucose uptake per fiber
This "metabolic remodeling" of muscle may contribute to improved insulin sensitivity independent of total lean mass changes. The muscle you keep becomes metabolically better, even if there's less of it[1].
[1] Pirkmajer S, et al. Front Physiol. 2023;14:1123456.
julia.endo said:Right, and protein targets should be set on a reference weight rather than current weight.
Saving this. It is the first explanation that did not require me to already understand it.
Dr.ObesityLA said:DEXA scan update relevant to lean mass: Scanned at months 0, 6, and 12.
Regarding lean mass: I accidentally injected my dose intramuscularly instead of subcutaneously last week (went in at wrong angle, too deep). Called my pharmacist — they said it's not dangerous but may absorb faster, potentially causing more GI effects.
Sure enough, had worse nausea that day. Lesson learned: pinch the skin properly and use the right needle length for your body composition.
PeptideDetective — Independent Peptide Analytics
Community-driven peptide testing and vendor rating platform. Transparent results. Unbiased analysis. Trusted by thousands.
View ResultsMikeFit_NJ said:Two DEXA scans eleven months apart: down 24kg total, of which the scan says 6kg was lean.
My endo's protocol for lean mass plateau: if weight loss stalls for 6+ weeks at current dose, we go through this checklist before titrating up:
- Food diary review — is intake creeping up?
- Protein check — minimum 100g/day
- Activity audit — steps + resistance training
- Sleep quality — poor sleep kills GLP-1 efficacy
- Stress/cortisol management
Only after addressing all of these do we increase the dose. Often fixing one lifestyle factor restarts progress without needing more medication.
Moderator note: leaving this open. It is being argued well and the disagreement is the useful part. Tagging this one for the weekly digest.