Make the next check-in useful
Upload a photo to LeanLens, get a confidence-aware read, and use the article framework to choose one practical next step.
What each record can show
| Record | What it describes | Interpretation limit |
|---|---|---|
| DXA lean soft tissue | A method-defined non-fat soft-tissue compartment | Not an isolated measurement of skeletal muscle |
| BIA lean / muscle estimate | A device-model estimate using electrical measurements and inputs | Device and preparation can affect comparability |
| Workout log | Completed load, repetitions and sets | Performance also depends on technique and conditions |
| Progress photos | Visible shape, posture and appearance | Cannot quantify muscle tissue or diagnose sarcopenia |
Keep lean mass and skeletal muscle separate
Fat-free mass is broader than skeletal muscle. Depending on the method, the report may describe lean soft tissue or use “lean mass” as shorthand for a calculated non-fat compartment. Water and other tissues are part of that context.
Read the exact report label before converting a change into “muscle lost.” The lean mass versus muscle mass guide explains the definitions and a simple calculation example.
What the STEP 1 body-composition analysis reported
The exploratory DXA substudy included 140 adults with overweight or obesity, with 95 in the semaglutide group and 45 receiving placebo. At week 68, the semaglutide group had lower total fat mass and lower total lean body mass, while lean mass as a proportion of body weight increased.
This is a semaglutide trial finding from a specified population and protocol, not a LeanLens validation, a personal forecast or an Ozempic-specific before-and-after result.
| Semaglutide-group measure | Reported change from baseline | Read the unit correctly |
|---|---|---|
| Total fat mass | −19.3% | Relative change in fat mass |
| Total lean body mass | −9.7% | Relative change in the lean compartment, not isolated muscle |
| Lean mass proportion of body weight | +3.0 percentage points | Share of total weight; can rise while absolute lean mass falls |
Make the next check-in useful
Upload a photo to LeanLens, get a confidence-aware read, and use the article framework to choose one practical next step.
Make records useful rather than merely frequent
For a workout record, save the exercise, load and completed repetitions so the same task can be reviewed later. For device estimates, save the model and preparation conditions. For photos, use the same camera setup and original dates.
Do not average unlike methods into one muscle trend. Follow the body-composition record template and photo checklist, then use the app comparison to choose the record owner you need.
Limits and safety
This article explains record-keeping and measurement limits, not medical advice. LeanLens does not diagnose muscle loss or evaluate treatment. Discuss medication and body-composition concerns with a qualified clinician.
FAQ
How can lean-mass percentage rise while lean mass falls?
A percentage is a share of total body weight. If fat mass decreases proportionally more, lean mass can represent a larger share despite an absolute decline; the STEP 1 exploratory analysis reported this pattern.
Does the study show that 9.7% of body weight was lost as muscle?
No. The reported −9.7% was a relative change in total lean body mass, not a percentage of starting body weight and not an isolated skeletal-muscle measurement.
Can photos detect sarcopenia?
No. Clinical assessment is needed; a photo comparison or physique score cannot establish that diagnosis.