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Understanding Lean Body Mass
Formula
Lean body mass (LBM) is everything in your body except fat: muscle, bones, organs, water, and connective tissue. Knowing your LBM helps determine protein needs and set realistic body composition goals.
The simplest method is LBM = Weight x (1 - Body Fat%). The Boer formula estimates LBM from height and weight without needing body fat percentage, using sex-specific coefficients.
Common use cases:
- Calculating protein needs based on lean mass
- Tracking muscle gains during training
- Setting body recomposition goals
Frequently Asked Questions
Maria Gonzalez
Registered Dietitian, RD, MPH
Maria is a Registered Dietitian with a Master's in Public Health. She focuses on evidence-based nutrition assessment tools including BMI, calorie calculations, and body composition analysis.
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