BMR (Basal Metabolic Rate)

Basal metabolic rate accounts for approximately 60-70% of your total daily energy expenditure. It includes everything your body does automatically: breathing, blood circulation, cell regeneration, temperature regulation, brain function, and hormone production. In practical terms, BMR is the amount of energy your body would burn if you lay in bed all day doing nothing. Typically, a woman's BMR is around 1300-1500 kcal and a man's 1600-1900 kcal per day.

Several factors affect BMR: age, sex, weight, height, and especially muscle mass. Each kilogram of muscle burns approximately 13 kcal per day at rest, while a kilogram of fat burns only about 4.5 kcal. This is why building muscle mass is one of the most effective ways to permanently increase your basal metabolic rate.

Understanding BMR is crucial for weight management. Overly strict diets - especially those under 1200 kcal per day - can reduce BMR by as much as 20-30%, because the body enters energy-saving mode. This means the diet works initially but slows down, and after stopping, weight returns even more easily. This phenomenon is called metabolic adaptation.

Practical tip: never eat below your resting calories long-term. You can estimate your BMR using the Harris-Benedict equation or online calculators. BMR is closely related to TDEE, which is your total daily energy expenditure, and to the concept of calorie deficit.

Last updated: March 30, 2026