VO2max from the Outcomes of Maximal and Submaximal Exercises - Essay Example

The estimation of the VO2max (maximal oxygen uptake) was examined using Multistage Fitness Test Mile Walk Test and Graded Exercise Test.Fourteen soccer athletes, all males aged between 20 and 42 took part in the exercise. It was hypothesized that it was possible to measure VO2max by using the results obtained from the maximal and submaximal exercise tests. The most perfect VO2max values were estimated from the association between the HR and VO2 in a submaximal exercise that was extrapolated to the age-estimated HRmax. For Graded Exercise Test, the collection of data was done on a continuous basis for VO2, RER and ventilation. The retrieval of all values was done on single breath measurements. The measurement of the heart rate was also done continually by the use of telemetry. For 1-Mile Walk Test, the VO2max was measured using a treadmill protocol which included running or walking at a speed that was self-selected, with a two and a half rise in grade every two minutes. Ability to estimate VO2max from the outcomes of maximal and submaximal exercises Introduction VO2max (maximal oxygen uptake) is actually considered as the best way of determining aerobic performance and fitness of cardio-pulmonary. It is believed that the best way of estimating maximum oxygen uptake is by directly measuring the uptake of oxygen during maximal exercise. However, this method is not an easy one due to the requirements of an all-inclusive medical check-up before the exercise and unrelenting supervision of the trial or test by a medical doctor with expertise in the treatment of the circulatory failure. Moreover, proper laboratory apparatus for directly measuring maximum oxygen uptake is quite costly and requires professionalism. Andersen, (1995) says that various methods have been devised to help in the prediction of VO2max from maximal or submaximal exercises. The methods were mainly done on the basis of the linear relationship between the exercise oxygen uptake and the power output and between oxygen uptake and the heart rate (HR). The tests of oxygen uptake have frequently been carried out on a cycle ergometer, which is a rowing ergometer or even a motor driven treadmill. There are also propositions for the measurement of VO2max without the exercise trials, such as from the ration between the HRrest and HRmax, or even from the self-reported predictor variables that do not involve exercise including the perceived functional ability of the participant to exercise, BMI, gender and habitual physical activity. According to Carey, et al (1995), in the past few years, despite the great technical development in the construction of the up to date or latest facilities for the measurement of the uptake of oxygen, we find that some novel methods of measuring VO2max have increasingly been designed and are regarded as very effective, especially in the researches on samples of large populations. However, these methods were usually applied in the field together with pre-selective researches focusing on the first determination of dispositions to the endurance sports. Witte, et al, (2001) say that nevertheless, there is not information that has been published about the estimation of VO2max from both the maximal and submaximal exercise trial on ski ergometer. This study aims at examining the accuracy of the prediction of the VO2max from maximal and submaximal exercise on three different methods namely; Multistage Fitness Test, 1-Mile Walk Test and Graded Exercise Test. Mitchell, (1997) claim that the MSFT (Multi-Stage Fitness Test), which is also known as the Beep Test or even Leger Test, is in the estimation of the VO2max of an athlete. The measurement of VO2mx is done in ml/kg/min. This is a very common and widely accepted in-season and pre-season fitness examination for athletes. The minimal space and facilities requirement has made it attractive for several coaches. Nonetheless, the interval runs, which are part of the exercise, seem to be very challenging. However, it offers a very good spread in the outcomes, dividing or categorizing the athletes into various fitness levels. This gives a realistic quantitative examination of the fitness levels on an individual and also that of the team. Pascoe, (1993) assert that the 1-Mile Walk Test is a method of fitness testing that was designed in the research laboratory of Dr. James Rippe, to test how aerobically an individual is. Aerobic fitness generally indicates how fitness a person is. Cox, et al, (2002) assert that the Graded Exercise Test is a tool used for the general screening in establishing the response of the heart to exercise. The hears usually contracts in a regular manner as a result of systematic spread of the electrical activity from one region of ‘pacemaker cells,’ which are the specialized cells to the remaining parts of the heart. Moreover, an electrocardiogram is the heart’s electrical activity surface mapping. There is a normal model of alterations in the heart’s electrical activity with exercise. However, with the presence of various kinds of diseases of the heart, we find that there will be different other models of changes in the heart’s electrical activity in the process of exercise. For instance, the response given in the rate as well as the regularity of the contractions of the heart are affected by certain types of the diseases of the heart, whereas in some others, the electrical activity’s spread within the heart is substantially affected. The change that results or ensues in the shape of the electrical activity’s surface mapping is then stored on the ECG. Methods Graded Exercise Test (GXT) Fourteen soccer athletes, all males aged between 20 and 42 took part in the exercise. All of them were taking part in the championship season practice during the test, and they had received training for three successive months without being interrupted and had at least 12 years of experience in competitive soccer at the amateur level. Besides competition, the weekly training involved team or skill training, resistance practice for a total of twenty hours in every week. There was a also reservation of uninterrupted sessions of aerobic running for the post-match recovery practicing days and took place only once in a week. Each and every subject read and then appended signature on the written informed consent. The subjects made two separate visits to the human performance laboratory. In preparation for the trials, the subjects were told to take a meal at least three to four hours before and not to take caffeine for at least a period of eight hours before the trials. Some other instructions for the subjects were to ensure that a daily diet was maintained. The diet was supposed to have high carbohydrates and also refrain from using drugs or even consuming alcohol the week before the test. Planning of the trials depended on the competition and training program of the participant such that there would be not strenuous physical activity in the past twenty four hours. All of the subjects completed the Graded Exercise Test that was conducted between 1pm and 6pm for the purposes of consistency. The test was conducted on a motorized treadmill, whereby every protocol had two-minutes stages whereas the running speed remained constant and grade increased two and half percent with every stage. The running speed was fix during a rehearsal and was linked with perceived exertion’s rating of thirteen to fourteen on the Borg scale. The participants ran the first stage at zero percent grade; and then the grade was raised until the volitional exhaustion was attained. The uninterrupted GXT was carried out continuously. Expired gas was collected continually during the exercise using an automated system that examined the volumes of expired gas and fractions of oxygen and carbon dioxide. A three-liter syringe was used in the calibration of the flowmeter and then a typical blend of CO2 and O2 was used in calibrating the analyzers of gas before every trial. The collection of data was done on a continuous basis for VO2, RER and ventilation. The retrieval of all values was done on single breath measurements. The measurement of the heart rate was also done continually by the use of telemetry. The subjects, after every GXT, walked at a slow speed for ten minutes. However, following the period of rest, the intensity was raised slowly over a one-minute until the last stage intensity was arrived at. During that time, the grade was raised two and half percent and the subject was told to continue with the exercise for two minutes. A plateau criterion for VO2 was included to establish whether it is true that the VO2max had been obtained in the test. Multi State Fitness Test (MSFT) This test involved a total of fourteen taekwondo players, all males aged between 20 and 42. The test was made up of twenty one levels, whereby every level lasted for about one minute. Every level consisted of a series of twenty meter shuttles, whereby the starting speed was eight and half km/hr, and the speed was being increased by half a kilometer per hour at every level. However, on the CD, one beep showed that they had reached the end of a shuttle and three beeps showed that the next level was started. All of the participants have a background of training of about two to three years. The demonstrations of the tests were done to the subjects before the real administration and they consented to the statement of informed agreement. All institutional policies concerning the human subjects in research were followed. The maximum oxygen uptake of every participant was measured by both direct and indirect methods, at an interval of four days by means of random sequencing. Participants had to rest for about thirty minutes before the test for the rate of pulses and pulmonary ventilation to stabilize. They took light breakfast two to three hours prior to the test and avoided any tiresome physical activity for the whole period. They began to run back and forth on a twenty meter course at a first speed of eight and half kilometers per hour which got increasingly faster; that is half a kilometer per hour, according to a speed dictated by CD. One-Mile Walk Test Fourteen individuals, all males aged between 20 and 42 took part in the exercise. Every participant had to complete a short medical questionnaire that was designed for the screening of orthopedic and cardiovascular challenges to brisk walking. All of the participants were healthy to take part. They were all weighed and then prepared for EGC monitoring before testing. The VO2max was measured using a treadmill protocol which included running or walking at a speed that was self-selected, with a two and a half rise in grade every two minutes. The trial was ended when the participant could not continue any longer. Every participant did a minimum of 2, 1-mile walks on a marked track. They walked as fast as possible. Results and Discussions The results obtained from the current research show that the prediction of VO2 can be done with level of accurateness both from the submaximal exercise tests from the association between HR and the uptake of oxygen or even HR and power output and also from the maximal tests without the measurement of uptake of oxygen on the basis of the relationship between maximal power output and VO2max. It is the first trial to estimate the maximal oxygen uptake from the outcomes of the ergometer. The prediction of the VO2max with high level of accurateness without the measurement of oxygen uptake was possible due to the very strong relationship between the uptake of oxygen and power output. In addition, it should be emphasized or noted that the participants were well acquainted with the exercise test, which certainly favorably had effects on the accurateness of the estimation of the VO2max. The outcomes of the study show that the commonly used methods produce patently decreased VO2max values in the groups examined. It is good to note that the accurateness of the estimation of VO2max by using Multistage Fitness Test, 1-Mile Walk Test and Graded Exercise Test was the same as those that were obtained by previous researchers such as Andersen L.B. et al, (2008) who established that the difference between the values of measured VO2max and those that had been predicted were equal to 2.9 percent and 8.1 percent. Conclusion It is true that the outcomes of the three tests show that the prediction of VO2max is possible from the outcomes of maximal and submaximal exercises. The accurateness across all the tests were standard. The most perfect VO2max values were estimated from the association between the HR and VO2 in a submaximal exercise that was extrapolated to the age-estimated HRmax. References Andersen K. 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