Basal metabolic rate (BMR) – The BMR is the minimum level of energy we need to use to maintain vital functions of the body. To accurately measure a person’s BMR, scientists make them fast (so there’s no digestive activity) and then lie motionless in an environmental chamber. Resting metabolic rate (RMR) is slightly higher than BMR, it’s usually no more than a 10% difference. Small amounts of movement, different environments, and digestion will affect RMR.
Thermic effect of feeding (TEF) – Digestion, absorption and assimilation of ingested food / nutrients is an active process — it takes energy. The very act of eating food increases the metabolism. TEF is usually around 10% of total daily energy expended. It can be affected by other factors, such as insulin resistance, which lowers TEF.
Exercise activity (EA) – The energy used to perform purposeful exercise (like going for a run, or doing a gym workout) is typically called EA.
Non-exercise activity thermogenesis (NEAT) – Non-exercise activity thermogenesis (NEAT) is another part of metabolic rate. This is all the daily-life movement that isn’t deliberate exercise. This is includes any physical and mental activity we do for our daily sustenance.
Total daily energy expenditure (TDEE)
All metabolic and movement activities make up our total daily energy expenditure (TDEE).
TDEE = BMR + TEF + EA + NEAT.
Refer to above link. This is one of the best TDEE calculators. Using this you can calculate your daily calorie requirement whether you want to lose weight or gain muscle or just maintain the current body composition.
The results are is a close approximation and we need to see how it works for us for few days by doing trial and error. We need to make minor adjustments here and there.
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