| Activity Tier | Multiplier | TDEE Calorie Target |
|---|---|---|
| Sedentary (Desk Job) | x 1.2 | 1,948 kcal |
| Lightly Active (1-3 days/wk) | x 1.375 | 2,232 kcal |
| Moderately Active (3-5 days/wk) | x 1.55 | 2,516 kcal |
| Very Active (6-7 days/wk) | x 1.725 | 2,800 kcal |
| Extra Active (Athlete/Heavy Labor) | x 1.9 | 3,084 kcal |
Metabolic Equations Compared
BMR calculators evaluate energy requirements based on mass parameters, age factors, and sex biology. The two primary models utilized clinically are outlined below:
1. Mifflin-St Jeor Equation (Modern Standard)
Considered the highly trusted contemporary gold standard for baseline metabolism calculations:
Female: BMR = (10 × W) + (6.25 × H) - (5 × A) - 161
2. Revised Harris-Benedict Equation (1984 Revision)
A classic biological formula revised in 1984 to tightly reflect physical outputs:
Female: BMR = 447.593 + (9.247 × W) + (3.098 × H) - (4.330 × A)
Where: W represents Weight in kg, H is Height in cm, and A is Age in years.
Frequently Asked Questions
Basal Metabolic Rate (BMR) represents only the baseline energy required to keep vital organs working in a zero-activity state. Total Daily Energy Expenditure (TDEE) is BMR multiplied by your physical activity level factor (representing active motion, exercise, and digestive thermal effects).
Yes. BMR is heavily influenced by lean muscle volume. Since muscle tissue is highly active metabolically compared to fat tissues, increasing muscle mass through physical strength training elevates baseline resting calorie burning limits permanent-wise.