Victoria NewburyLab Section: Tuesday 1:00 PMDate: 3/7/14Ben HoffmanLab Report 3; Maximum Oxygen ConsumptionINTRODUCTION:VO2 max is the maximal amount of oxygen that can be consumed by the body despite anyincreases in exercise intensity and is an indicator of aerobic fitness level. Energy expended above this level of oxygen consumption is performed using anaerobic respiration. VO2 max is limited by the ability to consume oxygen and the ability to deliveroxygen to the cells in the body. A limiting factor for delivery of oxygen is that the body needs to remove carbon dioxide from the system via hemoglobin. During intense exercise, the amount of carbon dioxide is greatly increased. Because oxygen is also carried by hemoglobin, there is competition to bind to hemoglobin, thus limiting the amount of oxygen that can be delivered. Oxygen delivery is also limited by cardiac output. Cardiac output is the amount of blood being pumped by the heart per minute and calculated by multiplying heart rate by stroke volume. The more blood being pumped by the heart per minute, the more oxygen that canbe delivered. However, stroke volume can only increase until about 40% of VO2 max. Therefore, increases in cardiac output are more reliant upon increases in heart rate.Maximal heart rate can be calculated for individuals based on their age subtracted from 220. Oxygen utilization is dependent upon the capabilities of the cells. Cells that are better adapted to exercise will be able to utilize more oxygen. Adaptations include increased size and number of mitochondria, increased capillary density, improved aerobic enzyme activity, and muscle perfusion. Cellular adaptations occur with training levels, the more training an individual has, the better their adaptations. Oxygen utilization can be calculated using the formula for AVDO2. AVDO2 is the difference in oxygen content between arterial and venous blood. The arteries carry blood away from the heart (either tothe lungs or to the rest of the body) and the veins carry blood to the heart (from the lungs or from the body).The purpose of this lab is to calculate the VO2max of a participant using two methods – one method that predicts her VO2max using a regression equation and the other calculatesher actual VO2max using a cycle ergometer and an incremental exercise test. As the average VO2max for a female college student is 40, it is predicted that the participant willbe slightly above 40. She is considered active as she runs 3-5 miles, five days per week. However, the fact that the test is performed on a cycle ergometer may impact her score slightly as she is more accustomed to running. Using a cycle ergometer may require her to use different muscles than she is used to or to use certain muscles more than others. METHODS:Before starting the lab, jobs were assigned to group members. The responsibilities included setting resistance, time keeping, recording heart rate, medcart reporter, recordingdata, RPE director, and cheering squad. The person setting resistance needs to increase the resistance by 1 after every minute of exercise. The person keeping time needs to alert the other group members (resistance setter, heart rate recorder, medcart reported, RPE director) when to report or record necessary data. The person reporting heart rate needs totake the heart rate every 30 seconds. The medcart reporter needs to note the volume of oxygen consumed, volume of carbon dioxide expended, and RER every 30 seconds of thetest. The person recording data listens to the medcart reporter, heart rate reporter, and RPE director for data and records it. The RPE director uses the Borg scale and periodically asks the participant what they believe their level of physical exertion to be. The cheering squad is important at the end of the test – they need to encourage the participant to finish. The participant’s characteristics were then recorded for consideration during analysis after the test. Using this information, we calculated a predicted VO2max using the regression equation listed in the calculations section of the lab report. We then set up the cycle ergometer to appropriately fit the participant, (attempted) to put a heart rate monitoron the participant, and set up the participant’s breathing mask. Once the medcart was adjusted, the participant then began to pedal at 60 Watts with no resistance for about two to three minutes. After this warm up, resistance was increased by 1 after every minute of exercise. During this process, it is important to watch the RER for when it reaches or goes above 1.1. This signifies that the participant is using anaerobic systems and hasreached their VO2max. There will also be a corresponding plateau on the medcart graph. This signifies that the participant can’t consume any more oxygen at a given time despite their increases in exercise intensity. Heart rate will be near max levels when the participant has reached their VO2 max. After every minute of exercise, the participant is also required to indicate their number of physical exertion on the Borg scale. This gives us an idea of how hard they think they are working and can clue us in on when they will reach their VO2max. Once the participant feels that they can are at their max physical exertion level, it is important to cheer them on to push until they finish that minute at a certain resistance level. The longer they are able to maintain exercise, the more accurate the data will be. After finishing this bout of exercise, they should stay on the bike and peddle with no resistance for several minutes in order to cool down.RESULTS:Table 1. Participant CharacteristicsGender Age Weight Height Training StatusParticipant 2 Female 21 170 cm 63.6 kg Runs 3-5 Miles, 5 daysper weekTable 2. Results from actual and predicted maximum oxygen consumptionPredicted VO2max Actual VO2 max Percent Difference(ml/kg/min) (ml/kg/min)Participant 2 41.5 44.2 6.1%Table 3. VO2, VCO2, RPE, and relative VO2 over timeTime Vo2 Vco2Relative VO2 (ml/kg/min) RPE:30 0.43 0.42 6.7610062891:00 0.35 0.38 5.5031446541:30 0.44 0.44 6.9182389942:00 0.48 0.42 7.5471698112:30 0.76 0.58 11.949685533:00 0.94 0.74 14.77987421 83:30 1.03 0.92 16.194968554:00 1.16 1.04 18.238993714:30 1.46 1.33 22.955974845:00 1.63 1.55 25.62893082 115:30 1.67 1.64 26.257861646:00 1.78 1.79 27.987421386:30 2.04 2.17 32.07547177:00 1.94 2.04 30.50314465 137:30 2.32 2.62 36.477987428:00 2.68 3 42.138364788:30 2.58 2.9 40.566037749:00 2.68 2.96