exphysass#2 - IPHY 4650-141 Assignment #2 February 3rd,...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
IPHY 4650-141 Assignment #2 February 3 rd , 2008 Metabolic Rate Laboratory Report Questions 1. Can indirect calorimetry be utilized to determine the energy expenditure for all types of physical activity? Why or why not? Use a specific example to defend your answer and include a clear explanation of how indirect calorimetry works. (4 pts) Indirect calorimetry cannot be used to measure all types of physical activity. Indirect calorimetry uses the measurement of oxygen to indirectly measure metabolic rate. Therefore, metabolism needs to be predominately aerobic. For example, weight lifting is mainly an anaerobic activity, which does not require oxygen. It is not possible to measure the full metabolic rate during weight lifting without oxygen; using indirect calorimetry would not provide a precise estimate of metabolic rate. (Book PG 57) Indirect calorimetry measures oxygen uptake by an organism using either a closed or open circuit spirometry. In a closed circuit, the subject breathes in and out of a chamber with a fixed amount of oxygen. (Class notes 1/22). Oxygen consumption rate is determined by the rate the oxygen is used up in the chamber (lab manual). During closed circuit spirometry, there is no oxygen exchange with the outside air. In open circuit spirometry, the rate of oxygen consumption is calculated by subtracting the amount of oxygen expired from the rate of oxygen inspired. In order to obtain these values, the subject breathes into a mouthpiece that allows atmospheric air to be inspired and the expired air to go into the Douglas bag. The gas analyzer analyzes the expired air inside the Douglas bag, and the oxygen/carbon dioxide fraction is measured. The volume of air in the bag is measured using a volumeter. 2.
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 03/18/2009 for the course IPHY 4650 taught by Professor Robertmazzeo during the Spring '09 term at Colorado.

Page1 / 3

exphysass#2 - IPHY 4650-141 Assignment #2 February 3rd,...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online