Metabolism Activity

Overview

Engineering reference data for Metabolism Activity in physiology.

Key Formulas

Basal Metabolic Rate

$BMR \propto M^{0.75}$

Kleiber's law — metabolic rate scales with body mass.

Heat Loss

$Q = hA(T_{skin} - T_{air})$

Convective heat loss from body.

Variables

Metabolic Rate Data

Metabolic Rate Calculations

The metabolic rate can be converted between power per unit area (W/m²) and total power using the mean body surface area.

Total Metabolic Rate (Power): $Q = M \cdot A$ Where:

• $Q$ is the total metabolic heat production (W).
• $M$ is the specific metabolic rate (W/m²).
• $A$ is the body surface area (m²).

Activity Factor: The Met (metabolic equivalent) value represents a multiple of the resting metabolic rate. $\text{Met} = \frac{M}{58}$ (Note: 58 W/m² is a common approximation for the resting rate (1 Met) for a seated, relaxed person).

Key Definitions

• Met (Metabolic Equivalent): A unit used to estimate the metabolic cost of physical activity. One Met is defined as the metabolic rate at rest, approximately $58 \text{ W/m}^2$ or $50 \text{ kcal/hr}$ for an average adult.
• Mean Body Surface Area: The typical surface area of an adult human body is approximately 1.8 m². This value is used to convert between specific metabolic rate (per unit area) and total metabolic power.

Interactive Charts

References

• Original Source