Exercise Physiology Lab Report

PURPOSE: The purpose of this lab was to predict maximal oxygen uptake during sub-maximal exercise and using a regression equation. More than one protocol can be used to determine an individuals VO₂ max. During this lab the YMCA bicycle test will be used to gauge what the subjects maximal oxygen consumption is without having to conduct a maximal exercise test. An individual’s maximal oxygen utilization capacity is very important in gauging how aerobically fit the individual is. It’s the best indicator in determining a person’s aerobic power and how well they can endure dynamic muscular activity. The two factors that determine an individuals VO2 max is the capacity with which they can deliver oxygen to the necessary cells in the body and how well they can utilize this oxygen available in their system. An individual’s maximum oxygen delivery is directly correlated to their oxygen carrying capacity and their cardiac output (Q). Cardiac output (Q) is the volume of blood being pumped by the heart every minute and is calculated by multiplying the stroke volume (SV) by heart rate (HR). The heart rate is the number of times the heart beats per minute. The Stroke volume (SV) can be defined as the volume of blood being pumped from the ventricle during a heartbeat. Certain individuals, such as older people, are not capable of safely undergoing a max test. Some healthy individuals don’t have the will power to endure the activity necessary long enough to obtain an accurateVO₂ max. For these reasons it’s sometimes very helpful and more advantageous to be able to determine an individual’s maximal oxygen consumption through sub-maximal activity.

METHODS: Subject characteristics were recorded: height (cm), weight (kg), age (year) and gender. The oxygen and carbon dioxide gas analyzers were calibrated and the environmental conditions: room temperature (°C), humidity (%), and barometric pressure (mmHg) were recorded. The subjects characteristics and environmental condition data were all entered into the computer. A polar heart rate monitor was placed around the subjects chest to record the heart during each bout of exercise. Seat height was adjusted on the cycle ergometer. The subject performed a sub-maximal exercise test on a cycle ergometer. Two bouts of exercise were performed; one at .5 kg workload and the second at 1.5 kg workload. A metronome was used and set so that the subject would maintain a pedal speed of 50 rpm. Each bout lasted 3 minutes and the heart rates recorded needed to be between 110 and 150 beats per minute. After the subject completed the test they were instructed to pedal for one minute to cool down. Using the values obtained during this experiment and the subject characteristics recorded earlier in lab the subjects maximal oxygen consumption was calculated using the regression equation shown below. The responsibility of the prep crew is to ensure that all the materials necessary are available for the experiment. They make sure the subject is ready for the start of the experiment as well .The clean up crew during the experiment is responsible for making sure all lab materials are put away and cleaned properly to ensure safety in the lab.

RESULTS: At the .5 kg workload the subjects heart rate was 131 bpm and at the 1.5 kg workload the heart rate was 148 bpm.

RESULTS:

Subject 1

Height: 183cm

Weight: 206lbs Þ 93.64 kg

Age: 21

PAS 5

Sex: Male

Workloads Heart Rate

0.5 kg Þ 150 kpm

131 Beats Per Minute

1.0 kg Þ 300 kpm

148 Beats Per Minute

YMCA Predicted VO2 Max = 1.75 L/min

(1.75 L/min)( 1000ml/1L) /(93.64 kg) = 18.69 ml/kg/min

Regression Equation Predicted VO₂ Max – 34.142 + (0.133 * AGE) – 0.005 (AGE2) + 11.403 (GENDER) +1.463 (PAS) + (9.170 * HEIGHT) – (0.254 * BODY WEIGHT)

= 46.45ml/kg/min