Maximal Oxygen Uptake and Body Composition
Lab Section: Wednesday 2:30
Due Date: October 14, 2009.
The human body can easily maintain energy production levels for everyday activities. As the activity level (or power output) is increased, the body must find a way to increase its energy production in order to remain in physiological equilibrium. During prolonged exercise, the body uses mainly aerobic metabolism to satisfy the adenosine triphosphate (ATP) requirement. As the body begins exercise, or transitions from a lower power output to a higher power output, this oxidative phosphorylation pathway cannot be turned on fast enough to deliver required ATP levels to the mitochondria. In this case, anaerobic glycolysis supplies the required substrates for ATP production until the aerobic pathway is able to increase the amount of oxygen reaching the muscle, and therefore the amount of ATP being produced.
A person’s VO2 max is defined as their maximum rate of oxygen consumption during aerobic metabolism. VO2 max is a measure of an individual’s full aerobic capacity and therefore considered to be the best indicator of cardiorespiratory endurance. The greater VO2 max a person possesses, the more oxygen they are able to deliver to the muscle and convert into ATP. During a VO2 max test, it is advantageous for the subject to use the aerobic pathway of ATP production, as it is a measure of aerobic capacity.
In this lab period we also focused on body composition and calculation by using Bioelectric Impedance Analysis (BIA). This method is based on the measurement of body density by using a small A.C. current. The current is sent from electrodes at the dorsal surface of the hand and foot and are received at the styloid process and lateral malleolus. The impedance of the current is then converted into body density. Electrolyte imbalances, depletion of muscle glycogen, temperature and hydration status are all...