VO2 Max and Aerobic Power

Oxygen is nonpareil of the vital elements of carriage because it acts as a fuel for aerobic respiration, which is the heartiness source in all organisms (the other fuel being glucose). With out(a) nil from respiration, organisms simply die. As an organism (in this shield me, a human) does sue, it motives more zip fastener. Thus it depart need more fuel and particularly more oxygen since glucose flip the gate be stored in the body. The oxygen intake increases as the rate of work d single increases, up to a limit cognise as your VO2 scoop shovel.VO2 liquid ecstasy is the soapimum volume of oxygen uptake (hence the V in VO2) whatevervirtuoso croup use. It is careful in milli ls per elegant per kilogram of body mass (mlO2 min-1 kg-1). pot who are more couple need higher VO2 pocket set and howevert exercise more intensely than those who are not rattling fit.Factors Affecting VO2 MaxThe physical limitations that restrict the rate at which vital force digest b e released aerobically are dep nullifyent upon The chemical ability of the t finaleinous cellular tissue system to use oxygen in br from individually 1 down fuels and, The combined ability of cardiovascular and pulmonary systems to transport the oxygen to the muscular tissue system.1The AimVO2 max can be measured in a variety of ways1. The aim of this experiment is to determine out the pass ons VO2 max and then covert it to the congeries aerobic magnate take.The modeVO2 max can be measured fairly accurately by doing a shuttle work style riddle ( bashn as The Multistage fittingness Test A.K.A. The Beep Test). Basically, someone has to run a 20 add together leading at the starting race of 8.5 kmh-1 for one dainty. at a beat the person finishes the 20 meter star, they must run back at the homogeneous speed, and thus we get an oscillating condition from one end of the track to the other until the minute is over.The speed is increased by 1 kmh-1 either minute (so after one minute of running at 8.5 kmh-1, the person must run the minute minute at 9.5 kmh-1). The comparable pattern is repeated only this magazine, because the person (the exposed) is running at a higher speed during the same amount of succession (one minute), they are firing to cover a larger distance and indeed more of the 20 meter electric circuits (in hypothesis anyway).This fact only works in theory because will most of the speeds, the athletic field can not run a set (whole human body) number of circles in exactly one minute. It turns out that if the progeny runs at 8.5 kmh-1 for one minute, they will cover 7.08 thrashs. This is impractical (how can you itemise that the discipline ran 7.08 laps) and so the number of laps must be rounded up or rounded down to an integer number of laps. in one case a set number of integer laps are set, we work out the time interpreted to run the integer number of laps. (Refer to columns 5 and 6).The caseful continues running until he or she can no largeer keep up the pace. The speed that the airfield nourishs (i.e. the speed before the speed that the subject stops on) is known as the Maximum Aerobic Speed (MAS) and is measured in kmh-1. Once we defy the MAS, we can work out the VO2 max in the pastime formulaVO2 max = 31 + 3.2 x (MAS Subjects Age years) + 0.15 x MAS x AgeThe unit for VO2 max is mlO2 min-1 kg-1.(Note The above formula is a transition formula developed by researchers, to give an accurate measure of VO2 max. See Activity pall 26)After calculating the VO2 max, we can turn it to maximum aerobic power output signal. Because the subject will be working with a high competency output, running requires a lot of energy the only way to keep going is by aerobic respiration. anaerobiotic respiration doesnt provide the high amounts of energy that are needed in such exercises, especially for longer periods of time e.g. ten minutes.For every litre of oxygen consumed, the subjects bodybuilde rs use 20kJ of energy. The total amount of oxygen consumed in a minute is the VO2 max multiplied by the body mass of the subject. This gives us the total oxygen intake of the subject in ml per minute (mlO2 min-1), since VO2 max is millilitres of oxygen per kilogram of body mass per minute. Once we tolerate the total oxygen intake in mlO2 min-1, we multiply it by 20 (if 1 litre gives 20,000 J, then 1 millilitre will give 20 J) to get the total amount of energy apply (i.e. power) in Joules per minute, (J min-1).Power (J min-1) = VO2 max (mlO2 min-1 kg-1) x Body Mass (kg) x 20 J mlO2-1Power (W, Js-1) = Power (J min-1) 60 s min-1Conventionally, the power output is measured in Watts per kilogram of body mass, W kg-1 (See card 3 on Pg 37 of the text book, Salters Horners Advanced Physics), therefore we would need to cleave the total power by the subjects mass. However the aim of the experiment is to find out the total aerobic power output. (At least that is what the Activity s chann ellery 26 says, under the last bullet point in the outline section) This means that there is no need to divide the total power output by the subjects mass. We just leave the total power output in Watts.(For Prepared patterns and An Interactive VO2 max calculator, See File Formula Input Form.xls)Interestingly, the test given on the website1 for calculating VO2 max (look for The Multi-Stage fittingness Test) differs in some ways from the one suggested in Activity Sheet 26. One of the differences is the increase of the speed is0.5 kmh-1 every minute, not 1 kmh-1. Also, if the subject doesnt wind up a whole minute at the speed of 15.5 kmh-1, for good example if the subject managed to complete 3 out of the 13 laps, then the subject would have a different (lower) VO2 max than if 10 laps were completed.Later on, I will discuss this issue and other differences in more period (Under the Evaluation).The Table (Table 1)If you refer to Table 1 (File Table 1.xls) you will collect all of th e information needed and all of the calculations have been done beforehand. I compiled this table using Microsoft Excel(r). at a lower place is a brief explanation of the table. newspaper column 1The speed of the subject, in kmh-1. tugboat 2The speed of the subject given in ms-1. To convert speed from kmh-1 to ms-1, we multiply by 1,000 (converting km to m) and divide by 3600 (60 x 60 is converting hours to seconds). Simplified, converting kmh-1 to ms-1 we multiply by 10/36. Thereforetower 2 = mainstay 1 x 10/36Column 3The time taken to complete one lap can be worked out by the down the stairs formulaVelocity (ms-1)= Distance (m) cartridge holder (s), if we re-arrange the formula to rile time the subject we getTime (s) = Distance (m) Velocity (ms-1).The distance is of one lap is 20 m and the velocity has been calculated in Column 2. Column 3 is justColumn 3 = 20m Column 2.Column 4This is the number of laps do in one minute (60 seconds). If I know that it takes 8.47 s to run one lap, I can calculate the total number of laps make in 60 seconds be dividing 60 seconds by the time taken to run one lap. So? of Laps in 60 seconds = 60 seconds Time Taken to Run One LapColumn 4 = 60 s Column 3Column 5This is just Column 4 rounded up or down to give us an integer number of laps. It means I dont have to deal with 7.08 laps and suchlike.Column 6This is the time taken to run the integer number of laps. We calculate this by multiplying the time taken to run one lap (Column 3) by the integer number of laps (Column 5).Time to Run integer ? of Laps = Time to Run One Lap x Integer ? of LapsColumn 6 = Column 3 x Column 5Column 7Since we know that each lap is 20 meters and we know how many integer laps the subject will run, we can find out the total distance covered during a proper(postnominal) speed by multiplying 20 meters by the integer number of laps. do Distance Covered During a Speed = 20 m x Integer ? of LapsColumn 7 = 20 m x Column 5Column 8Column 8 is the a dditive distance ran. Here, the distances are added up (accumulated) so that we know the total distance ran through the whole activity. The cumulative distance is the total of the previous distances (previous speeds) plus the distance of the authoritative speed.Column 9Column 9 is the cumulative time taken for the activity. It is in seconds and works in pretty untold way as Column 8, i.e. the times of the previous runs are added to the current run to give the total cumulative time.Column 10This is the cumulative time presented in a more familiar and user friendly format, the minute second style. This is just here to give a sense of how long 840 seconds are.The Tape (or The Slideshow)In regularize to make the subject run at the times listed on the Table, I will need to prepare a tape or some sort of quantify device.After attempting to make a tape and failing miserably, I decided to use Microsoft PowerPoint(r) rather (making the tape proved to be a long winded, boring and unpro ductive exercise), because, with PowerPoint, I can set time intervals between gliding transitions and add sounds on every slide transition, making it a visual as well as an aural aid and I can have a lot more fun making it (i.e. I can have lots of interesting and slightly odd sounds on the slide show)I as well as realised that it would be more helpful (to the subject) if I had a sound in the middle of each lap and to have a crisscross on the middle of the lap (10 meters). In case the subject is going too slowly and doesnt reach the middle marker when the middle bleep sounds, they can speed up to reach the end of the lap in time.However there is a slight evil with using PowerPoint because the transition periods can only be set to 0.1 of a second (1 d.p.) and the lap times are given to 0.01 of a second (2 d.p.) and some of the half laps are to 0.001 of a second (3 d.p.). Therefore I have had to alter the timing of the transitions slightly so that there isnt a cumulative error. For example, during the prototypic speed (8.5 kmh-1), it takes 4.235 seconds to complete half a lap, alone I can only have 4.2 and 4.3 as time intervals in PowerPoint, therefore I had to find a pattern that consisted of 4.2 and 4.3 time intervals to fit the 4.235 time interval as well as possible.This technique took preferably some time, however, using Excel helped greatly. With Excel, I could input different patterns (using 4.2 and 4.3 seconds) and opinion the sum automatically. If it wasnt right (i.e. if the total time wasnt come up the time in Column 6 in Table 1), I simply changed the pattern until I got the closest time.Also I decided that there wasnt a need to go beyond 13.5 kmh-1 because when we did a warm up to the test (a conformation of preliminary), none of the subjects managed to run over a thousand meters. In order for any of the subjects to complete the 13.5 kmh-1 speed, they would need to run at least 1100 meters, therefore there was no point in extending the prese ntation beyond that speed.(See Files Timing.xls for the pattern generating, and Timing Presentation.ppt, listen out for a treat during the last fewer slides)The Safety (Issues)It is always important to consider safety in any situation, and it is especially important in this type of activity where there is a fairly high risk of an accident and or an injury occurring. Below is a set of guidelines that the subject and others present during the activity should follow.The subject should aim with a five to ten minute warm-up period, before the test is started. It should consist of stretches and short runs where the subject should rapidly accelerate and then decelerate. This helps the subject to run better in the test and also helps avoiding any muscle cramps during the test.In the (relatively) unlikely all the samet of the subject falling, or hurting him/herself in any other way, the subject should stop running immediately. Also if the subject feels any pain or dizziness, they should s top. The subject should not continue with the test, even if they seem or appear to have recovered.The end pointsThe results are in the Result Sheet (unsurprisingly). The results were gathered from the experiment, which was conducted with ten subjects, including myself. They are in order of VO2 max.(The Results Table can be found in Results.xls)The EvaluationAfter complemental the experiment, I worked out the aerobic power of the subjects very easily, with the help of Excel. I personally found the experiment enjoyable and it my got the heart pumping (A somewhat rareness in physics, consider electricity ok, maybe pacemakers, and the way they electrically traumatise people who have had heart attacks with two funny looking plough things, not much else though).However, there were many problems I encountered while conducting the experiment. To obtain with, we couldnt find a 20 meter track anywhere in our school, considering the fact that there had to be a socket close by since my ti ming mechanism uses a computer (there are three sports halls in the school, but they were all busy). Therefore, I had to settle for a smaller 10 meter track. The fact that I had midpoint bleeps in the timing mechanism meant that each bleep (midpoint and full-length bleeps) was a signal for the subjects to reach the end of the 10 meter track. This meant the timing was not touched, however the experiment could have been bear upon greatly. (See the Miscellaneous Calculations section)Secondly, in the Activity Sheet, it says, For every litre of oxygen consumed, 20kJ of energy are transferred to the subjects muscles. However it fails to mention whether or not some of that energy is lost as heat and other ways of energy loss (e.g. fiction from the ground, the energy needed to stop at the end of every lap and even the energy needed to move the muscles themselves, i.e. contracting and restful of muscles). There are no suggestions or hints on how much of the energy is used to propel the subj ect. Although this can be calculated in the kinetic energy equation, EK = 1/2mv2, and the power equation P = ?E/?t . However, I suspect that these energy fluctuations are taken into account via the VO2 max formula.But even the formula itself isnt very accurate in my opinion. As I mentioned earlier, if two subjects managed to sustain the same MAS (Maximum Aerobic Speed) but one of the subjects ran more laps, then logically that subject has a higher VO2 max. This logicalness is not, in any way, included in the formula. On the website (See Note 1 of Reference) the tables show that if one of the subjects ran more laps during the same speed, that subject would have a higher VO2 max that if he/she managed to run a smaller number of laps. Therefore, I do not believe that the formula for calculating VO2 max on the Activity Sheet 26 gives a overcompensate numeric value of the subjects VO2 max. Although the experiment has shown that some of the subjects are fitter that others (i.e. the ex periment is correct qualitatively), it did not produce reliable figures with regard to the VO2 max of the subject.On the first of the Activity Sheets, Figure A26.2 shows a line graph of VO2 max for boys and girls at different ages. According to the graph, 16-year-old boys should have a VO2 max of 52-53 mlO2 min-1 kg-1. Ops (My VO2 max is nowhere near that, or at least the formula tells me that it is nowhere near that). It shows that I am not as red-blooded as I should be, considering that my mass is 85 kg Unlike Robert, who is a very healthy person and managed to run at a high enough speed to get a high VO2 max. (Although I should stress again my discredit about the numbers given by the formula)The Miscellaneous CalculationsA velocity-time slue of the subjects motion.Note the discipline under both of the curves should be equal since the same distance, 10 meters, is travelled. The distance is the speed multiplied by the time i.e. the area under the graph.AAs mentioned earlier, th e energy needed to propel a subject can be calculated via the kinetic energy equation.EK = 1/2mv2 and P = ?E/?tMy mass is 85 kg. If I ran one lap at 8.5 kmh-1 (which is 2.36 ms-1, Refer to Table 1), the energy needed isEK = 1/2mv2 so, EK = 1/2 x 85kg x (2.36ms-1)2EK = 236.7 JIf the above amount of energy were delivered by my muscles in one lap (10 meters, since that was the length each subject had to run) at 8.5 kmh-1, it would have taken 8.47/2 seconds (only half a lap, 10 meters). SoP = ?E/?t P = 236.7/4.235 P = 55.9 Js-1, WHowever, if I ran 20 meters, then the power isP = 236.7/8.47 P = 27.9 Js-1, WThe amount of energy accumulated while running a lap is then dissipated towards the end (of each lap) as the subject must come to rest i.e. the velocity is zero. Notice also that because the subject has to accelerate at the beginning of every lap, some extra energy is needed for that acceleration. The subject must accelerate every 10 meters because he/she has stop and then run in the o pposite direction.As the lap distance decreases, the power transfer increases. This shortage (of lap distance) will also cause the subject to accelerate and decelerate more often. Therefore, the smaller the lap distance, the larger the error could be (due to the fact that some of the energy is used up in accelerating). Using a 10 meter track instead of a 20 meter track could have affected the results because this meant more energy used in accelerating. It is therefore, justifiable to say that had the track been longer (i.e. 20 meters), myself and all of the other subjects could have been able to sustain a higher speed instead of the one that was achieved.