But first some terms and concepts…
In nutrition, a calorie is the amount of energy required to raise the temperature of 1 litre of water by 1 degree celsius
When your body converts calories in your food into energy, or makes chemicals that your cells need, to maintain life—to breathe, talk, walk or think
The number of calories you burn each day to keep your body ticking—measured by the heat your body exudes or level of carbon dioxide you exhale
LEAN BODY MASS (LBM)
Everything in your body that isn’t fat (bone, fluids, organs and muscles) is LBM. They determine your metabolic rate (MR), because they convert a lot more calories into energy than fat. More the LBM, more the MR.
Your body weight and metabolic rate are linked. Eating too many calories and not burning enough through activity can lead to weight gain.