Dr.PulmRoch said:Back pain as a lean mass side effect: not from the medication itself, but from rapid body composition changes.
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.
Dr.PulmRoch said:Back pain as a lean mass side effect: not from the medication itself, but from rapid body composition changes.
This is exactly what I could not find anywhere else. Adding it to my notes with a link back to this thread.
From the other side of the consultation, briefly.
Sharing my comprehensive lab data relevant to lean mass:
| Biomarker | Baseline | Month 3 | Month 6 | Month 9 |
|---|---|---|---|---|
| Weight (lbs) | 254 | 234 | 234 | 204 |
| A1C (%) | 7.4 | 6.4 | 5.9 | 5.6 |
| hsCRP (mg/L) | 9.0 | 3.0 | 1.5 | 1.0 |
| Triglycerides | 184 | 174 | 114 | 114 |
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.
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Shop Reference Standardstraveltech_sara said:Sharing my comprehensive lab data relevant to lean mass: Biomarker Baseline Month 3 Month 6 Month 9 Weight (lbs) 254 234 234 204 A1C (%) 7.4 6.4 5.9…
Second this.
traveltech_sara said:Sharing my comprehensive lab data relevant to lean mass: Biomarker Baseline Month 3 Month 6 Month 9 Weight (lbs) 254 234 234 204 A1C (%) 7.4 6.4 5.9…
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 | 247 lbs | 237 lbs | 214 lbs |
| Fat mass | 117 lbs | 67 lbs | 49 lbs |
| Lean mass | 155 lbs | 154 lbs | 151 lbs |
| Body fat % | 40% | 34% | 23% |
Lean mass preserved — actually GAINED 1-2 lbs thanks to progressive overload + 1.5g/kg protein. The lean mass discussion needs to include body comp data, not just scale weight.