How to Calculate Kleiber's Law
What is Kleiber's Law?
Kleiber's Law: metabolic rate scales with body mass as M^0.75. BMR = 70 × M^0.75 (kcal/day). Larger animals have lower metabolic rates per unit mass but higher absolute rates.
Step-by-Step Guide
- 1BMR = 70 × M^0.75 (kg)
- 2Heart rate ≈ 241 × M^-0.25 bpm
- 3Lifespan ≈ 11.6 × M^0.25 years
Worked Examples
Input
70 kg human
Result
BMR ≈ 1,688 kcal/day · HR ≈ 74 bpm
70^0.75=24.1; 70×24.1=1687
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