Lean Body Mass (LBM)

Your total weight minus fat — muscle, bone, organs, and water. Used to set protein targets and evaluate composition changes.

Educational reference only. The numbers on this page summarize public service regulations for planning purposes. They are not official medical, recruiting, or administrative determinations. Always confirm your status with a recruiter, commanding officer, or hiring agency using the official assessment.

Formula

LBM = weight (lb) × (1 − body fat %)

Healthy range

Varies widely with frame and training; a 180-lb man at 15% body fat has ~153 lb of lean mass.

Military & first-responder angle

Preserving LBM during ABCP weight loss is the difference between staying strong and getting weak — the reason programs pair calorie targets with strength training.

Calculator

Lean body mass from weight and an estimated body-fat %. Useful for tracking training progress.

Result

Lean body mass67 kg
Lean mass = weight × (1 − body-fat%). Re-estimate body-fat periodically; do not treat a single reading as exact.

Quick answers

How fast can I lose fat without losing muscle?
At a ~400 kcal deficit with adequate protein and lifting, expect mostly fat loss — roughly 70–90% of weight lost can be fat when training and protein are dialed in.

Related metrics