Chapter 56, Problem 1.4A

Summary Introduction

To explain:

Relationship between oxygen consumption and metabolic rate.

Introduction:

Basal metabolic rate (BMR) is a measurement of the minimal amount of energy needed to maintain vital bodily functions. In humans, BMR can be measured when a person is in a relaxed and awake state, reclined in a dark room at a comfortable temperature, having had nothing to eat for 12-14 hours, after a restful night’s sleep, and having had no exercise for at least one hour. To get a measure of metabolism, we perform calorimetry. Calorimetry is the measurement of changes in the state variables of the body.

Calculation of metabolic rate:

Oxygen consumption per minute: Convert seconds to minutes by dividing by 60 and then divide 10 mL by the time in minutes.
Oxygen consumption rate: {(O₂ mL per min) × (60 min/hr)} / animal weight = O₂ mL/g/hr
Metabolic rate: The factor 0.004825 converts mL O₂ into kcal of energy produced, the factor 1000 converts grams (g) to kilograms (kg).
O₂ mL/g/hr × 0.004825 kcal/mL × 1000 g/kg = kcal/kg/hr