Return to running after weight loss — need advice

julia.endo said:

There is also a quality change that the scan cannot see.

I read this differently from julia.endo, on substance rather than tone. I think this board over-worries about lean mass. Some lean loss is obligatory — you need less muscle to move a smaller body, and preserving mass you no longer need is not a health outcome. The question is whether strength and function held, and mine did.

NurseKim_ATL 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: Tirzepatide 10mg/wk, resistance training 5x/week, protein 1.5g/kg/day.

The improvements in lean mass are clearly reflected in these numbers. The inflammatory marker reduction (hsCRP) is particularly striking.

JennaRN said:

I think this board over-worries about lean mass.

Bone density monitoring on lean mass: DEXA bone density at baseline and month 12.

Lumbar spine T-score: -0.8 → -0.7 (stable to slightly improved)
Femoral neck T-score: -0.12 → -0.8 (stable)

No significant bone loss despite 65 lbs of weight loss. Key factors: adequate calcium (1200mg/day), vitamin D (5000 IU/day), resistance training 3x/week, and adequate protein. Weight-bearing exercise is critical for maintaining bone density during rapid weight loss.

One thing that is still open after NurseAsh_DET’s answer:

Whether resistance training and protein change the ratio or only the absolute amount?

OP back with an update, since a thread like this is useless without one.

Second scan under matched conditions came back with the lean number nearly a kilogram higher than the first, so a chunk of what I panicked about was hydration. Strength numbers were up throughout.