PharmD_Rodriguez said:Bone density monitoring on lean mass: DEXA bone density at baseline and month 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.
Dr.EndoEP said:Agreed on the ranges, with the condition that a single DEXA is not a measurement, it is one draw from a distribution.
Genuinely useful, thank you. I had the facts and not the framework. Sending this to two other people who asked me the same thing last week.
PharmD_Rodriguez said:Bone density monitoring on lean mass: DEXA bone density at baseline and month 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.
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Shop Reference Standardsadam_van said:Two DEXA scans eleven months apart: down 24kg total, of which the scan says 6kg was lean.
Sharing my comprehensive lab data relevant to lean mass:
| Biomarker | Baseline | Month 3 | Month 6 | Month 9 |
|---|---|---|---|---|
| Weight (lbs) | 266 | 251 | 226 | 201 |
| A1C (%) | 6.6 | 6.6 | 5.5 | 5.3 |
| hsCRP (mg/L) | 6.0 | 4.0 | 1.5 | 1.2 |
| Triglycerides | 236 | 146 | 126 | 106 |
Protocol: Semaglutide 2.4mg/wk, resistance training 3x/week, protein 1.4g/kg/day.
The improvements in lean mass are clearly reflected in these numbers. The inflammatory marker reduction (hsCRP) is particularly striking.
Moderator note: the sourcing question belongs in the vendor section and has been split out. Carry on.