Dr.ObesityLA said:

Muscle fiber type changes during GLP-1-mediated weight loss, relevant to lean mass: preliminary biopsy data suggests that weight loss shifts the…

Body composition tracking via bioimpedance on lean mass (InBody scan every 3 months):

Note: skeletal muscle mass dipped initially then recovered with consistent resistance training + high protein. The visceral fat reduction is where the metabolic magic happens.

EndoResFellow said:

Right, and protein targets should be set on a reference weight rather than current weight.

This is exactly what I could not find anywhere else. I will report back once I have actually tried it.

Dr.ObesityLA said:

Muscle fiber type changes during GLP-1-mediated weight loss, relevant to lean mass: preliminary biopsy data suggests that weight loss shifts the…

Dr.ObesityLA said:

...the muscle loss concern with lean mass...

This is a legitimate and well-studied concern. Let me put some numbers on it:

In STEP 1, approximately 39% of weight lost was lean mass. However, the Lundgren 2024 study showed that structured resistance training reduced this to ~25% lean mass loss.

Context matters: at BMI 35+, you're carrying excess lean mass to support the extra weight. Losing some lean mass is expected and not inherently harmful if you maintain adequate muscle function through exercise.

The solution isn't avoiding the medication — it's combining it with proper exercise and protein intake.

Dr.NutriCornell 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:

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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