Capacity 02 · Recover From Stress
Signal · ALMI

The muscle you carry into aging.

ALMI measures the lean mass in your arms and legs, normalized to height. It is the clearest readout of skeletal muscle reserve — and skeletal muscle is the organ of metabolic health, glucose disposal, strength, and independence into the later decades.


The ranges that matter

Four bands. One direction.

What matters most is the direction over time under the same conditions — is the number trending toward the Fit band, or drifting away from it? Your Radar scores every marker 0–100 on the same four-band continuum you see on your report: Fit (90+), Well (50–89), Short of well (26–49), Sick (25 and under). A score of 25 is the diagnosable line at any age. The values below are the age-40 reference — the bands shift with your age and sex, so use the calculator underneath for your own numbers.

Fit
≥ 9.1 kg/m² (M) · ≥ 7.6 (W)
Strong reserve, well clear of any sarcopenia threshold. A wide margin to spend over the next thirty years.
Well
7.6 – 9.1 kg/m² (M) · 6.1 – 7.6 (W)
Adequate now, narrower margin into aging. Worth actively building — muscle does not come back easily past 50.
Short of well
7.0 – 7.6 kg/m² (M) · 5.5 – 6.1 (W)
The Radar scores 25 at 7.0 (M) and 5.5 (W) — the sarcopenia thresholds. Function, insulin sensitivity, and injury resilience are all exposed.
Sick
≤ 7.0 kg/m² (M) · ≤ 5.5 (W)
Clinically low relative muscle mass. The reserve you draw on when sick, injured, or old is not there.
Unitkg/m²
Test typeDXA scan
Look atabsolute ALMI against age- and sex-adjusted bands

What it reveals

Muscle is the organ of healthy aging.

Skeletal muscle is not just what moves you. It is where most glucose is disposed of, where most amino acids are stored, and where the reserve lives that you draw on when you are sick, injured, or old.

After about age 30, humans lose muscle and strength slowly unless they actively work against it. The decline accelerates after 60. Sarcopenia — clinically low muscle mass — doesn't announce itself. It reveals itself when someone falls and can't recover.

ALMI normalizes the muscle in your arms and legs to your height, which makes it comparable across people. A higher ALMI at 40 predicts better function at 70 — not because you'll always have that muscle, but because the curve starts higher and declines from there.

This sits in Recover From Stress because lean mass is the tissue reserve that recovery draws on — muscle absorbs training load and rebuilds between doses, and a body with too little of it has less capacity to take a hit and come back. Everything you build now becomes the margin you draw on later.

On the floor If you are in your forties or fifties and ALMI is in the 'Well' band, treat that as an opportunity, not a reassurance. The cheapest muscle to build is the muscle you build now — and the reserve compounds for the next thirty years.

Coaches only

The intervention levers live with coaches.

The education above is open to everyone. The specific levers — what to actually do to move this marker — are part of the coaching program. Enter your coach password to unlock, or get in touch about becoming a coach.

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Coaching and education only. Not medical diagnosis or treatment. Excerpts welcome with attribution to metabolicradar.com.