Skeletal Muscle Index (SMI)
Diagnostic: Appendicular Lean Mass & Sarcopenia Screening
Biometric Data
[ Awaiting anthropometric data for sarcopenia risk calculation ]
MASS
Research: SMI vs Functional Aging
The Formula
The Skeletal Muscle Index (SMI) measures **Appendicular Lean Soft Tissue (ALST)** relative to the square of your height. Unlike BMI, which aggregates fat and bone, SMI isolates the functional engine. For the athlete 50+, this is the primary biomarker for mobility preservation.
Sarcopenia Prevention
Clinical thresholds ($<7.0$ for men, $<5.7$ for women) represent the "disability zone." Academic Athletes should target the high-performance tier to buffer against the 1-2% annual muscle loss typically seen after age 50.
- Male Elite: > 9.0
- Female Elite: > 7.5
Diagnostic Disclaimer: This calculation uses an ALST estimation based on total lean body mass. For clinical precision, a DEXA scan is required.