Assessment of usable and suitable tests for maximum physical power in workers

The physical and mental health of workers is very important in occupational health, one of the most important organs of the body is cardiovascular system or blood circulation. Various occupational factors affect it. Cardiovascular health in workers is an important item. Before doing physical work, such as exercise or work, it is necessary to determine the maximum aerobic capacity of individuals. However, this was not a matter for business for a few years ago, and it was only for professional athletes performing a series of aerobic tests before going to work professionally it was done. Today, the importance of this issue has been detected in physically active workers, but for some reason it is difficult to determine the maximum aerobic capacity of the workforce, but it can find a good place in physical examinations. Occupational physiology is contented cardiovascular system; heart and blood circulation and vessels such as arteries, veins and capillaries, respiratory system; lungs, musculoskeletal system and other related organs, but cardiovascular system has an important situation in this item. Heart beat, cardiac output, electrocardiogeraphy and its changes are main variables in tests and examination. Heart beat in many test has major importance; step and bike tests. Electrocardiography in treadmill tests is assessed. Changes of electrocardiography such as P wave, P-R, QRS complex, T wave, ST are assessed. Occupational physiology is one of the subject in ergonomic factors. Ergonimic factors are occupational physiology, anthropometry, environmental physiology, industrial psychology and biomechanic. Anthropometry is study on measurement of human body, it is used in making worker’s station. Environmental physiology is environmental factors such as temperature. Biomechanic is study on skeleton muscles and joints, working postures and lifting loads. Industrial psychology is study about stress in workplace and prevention of it.Occupational physiology was an important and must be assessed for many situation such as preplacement examination for workers, fitness for work or sport, periodic physical examination, return to physical work, impairment and disability assessment and calculation.Aim was determining the appropriate and suitable tests for determination the maximum aerobic power in working people in a review study, the objective of the study was determination the tests for calculation of the maximum aerobic power in workers according to jobs and ages.

Using the scientific resources up to day, validated and scientific websites related to medical sciences was conducted on the tests used to determine the maximum physical aerobic power of review research. In this study, the tests were divided into four major categories . The results of job and age were compared.The first group of tests performed by the standard step, the second group of tests performed by an ergometer bike, the third group of tests performed by the treadmill and the fourth group of tests that were not required by the special instrument.Determine the research question, determine the instructions for doing the study, review the texts, evaluate the information in the studies, analyze the findings and interpret it, so that the researcher can determine the appropriate tests in each case. All studies on the determination of maximum aerobic power in employed people from 1970 to 2018, review of texts in scientific books, journals and related scientific sites, motor searching such as Springer, Pubmed, Scopus, Google scholar, Elzevier, Wiley, Web of science, Medline, magazines and books on Sport medicine and Occupational health ,physiology and Occupational medicine, Behdasht ministry, international labor organization, occupational safety and health administration, national institute for occupational health and safety websites.  Based on the method of measuring maximum aerobic power, the name of the test and the type of job was searched. Assessing the information and results in qualitative and quantitative studies and analyzing the findings to determine the appropriate tests in each case. In this regard, the numerical scale was used.                                                                                   

The first set of tests performed by the standard step, the second group of tests performed by an ergometer bike, the third group of tests performed by the treadmill, and the fourth group of tests that are specifically designed to do without special instrument. The results of tests performed had differences from each other. Each test had indication and contraindication. Side effects were important and must be considered. Some contraindication were cardiovascular disorders; ischemic heart disease in acute phase, crisis of hypertension, respiratory; asthma attack and musculoskeletal diseases; hip osteoarthritis and rheumatism and fever in infection or inflammation disorders that could be affected on heart rate. Fatigue and chest pain or dyspnea during the test were indications for stopping the test. The most prevalent test in each group was Mc Ardle step test, Astrand Bike test, Bruce test and Cooper running test.Result of studies demonstrated, the first set of tests performed by standard steps, such as Quin’s or McArdle College step testing, performed this test in 3 minutes with steps of 104 steps, then measured heart rate per minute and placed in the formula the corresponding result was to calculate VO2 Max and then MET (metabolic equivalent of task). In fact, in all tests, the goal is to obtain these indices. It was recommended in moderate to heavy work and in young people. Another step test is Harvard step test, it was done in 5 minutes. The second set of tests performed by an ergometer bike, one of these tests, is the test of the Astrand bike. This test was carried out in six minutes of biking. We only need to give the bike the intensity, and eventually using the heart rate to calculate the maximum aerobic power. It was recommended in heavy work and young ages.The third group of tests performed by the treadmill were different. These tests were varied from common tests such as Bruce and Bruce modified, Balk and Nakhton by a moving tape. Usually, the time the person was on the tape is placed in the corresponding formula and the aerobic power of the person was obtained. Performing these tests requires a fairly high physical capacity. However, the conditions were different from each other, and the Bruce modified test and Nakhton are used for people who were less physically fit. It was recommended in pilot and diving and middle ages. The fourth category of those tests that did not require a specialty to do it, the Cooper Test, George Jog Test, and Rockport Walk Testing were among them. With a range of features such as running distance (Cooper), age, gender, weight, duration Running or Walking Time (George & Rockport) researcher could get the maximum aerobic power and calculate it. It was recommended in moderate work and adolescence and young people. Precition of test was an important some of test had more precision than others. Mc Ardle step test, Astrand bike test , Bruce test and Rockpport walk test had more precision than other in each group. Occupational health team should be calculated the VO2 max and metabolic equivalent of task for each worker and compared with standard amount and needed for physical job. Percent of metabolic equivalent of task to MET of workers was calculated and if it was lower than 40 percent it would be in low risk for health. But more than 40 percent had moderate to high  risk for health and must not placed worker on this job.This research worked on aerobic and other study should be done for anaerobic physiologic exams that could be help of occupational health team.

Using appropriate tests in appropriate situations could help in making better decisions for the employment. Each test was appropriate for some specific jobs and persons in different ages. It was important in occupational examinations. This study recommended the Mc Ardle step test for young people (19-30) in gaurding work, Astrand bike test for young people(31-44) in firefightering, Bruce test for middle ages in Pilot and Diving work and Cooper for adolescence in educational and sporting. The researcher recommended the tests in preplecement of workers in physical works but must be done under supervision because of side effects and having cardio- pulmonary resuscitation instruments and team. In some industries might be elected some tests, in this situation occupational health team must be determined the suitable examination. All of the results must be gathered and recorded in occupational health issues in occupational health center.Keywords: occupational physiology, aerobic power, employees