LEAN BODY MASS
Lean Body Mass is a term that is used in measuring physical fitness, body composition is used to describe the percentages of fat, bone and muscle in human bodies. Because muscular tissue takes up less space in our body than fat tissue, our body composition, as well as our weight, determines leanness. Two people at the same height and same body weight may look completely different from each other because they have a different body composition.
(Sources: National Institutes of Health/ Wikipedia)
