Methods: In this lab, indirect calorimetry was used to measure metabolic rate by calculating caloric expenditure by the measurements of oxygen consumption. The variables measured were the fraction of oxygen expired, the fraction of carbon dioxide expired, and the total volume of air inspired.
This experiment required the participation of two volunteers. First, the variables were measured variables while the two subjects were in a resting state. Readings were taken over a period of three minutes and averaged so that it could be assumed that the subjects were in a steady physiological state. After taking readings at a resting metabolic state, these variables were measured again while the subjects were performing light exercises: on a cycling bike and on a treadmill. The first exercise was on a cycle with 1 kp of resistance at 50 rpm. Data was measured in the third minute and recorded. This was followed by another three minutes on the cycle with 2 kp of resistance at 50 rpm. Again data was measured in the third minute and recorded. The second exercise was on a treadmill at 3.5 mph with no grade, followed by 4.0 mph at a 7.5% grade. Each session on the treadmill lasted three minutes and the data was measured and recorded in the third minute during both cases on the treadmill.
Once all of these measurements were collected and recorded for both subjects, the absolute oxygen consumption, relative oxygen consumption, absolute carbon dioxide production, the respiratory exchange ratio (R), and ultimately Caloric expenditure were all measured. Studying these calculations provide some insight into how much energy the body is using as well as what sources the energy is coming from.
Results
*Subject 1: Andrea Body Weight: 54.5 kg
Collected Data
FEO2 (%)
FECO2 (%)
VE=VI (L)
Rest
0.1743
0.0329
8.1
Cycle Work Rate 1
0.1651
0.0421
11.5