EXSS 376L PHYSIOLOGICAL BASIS OF HUMAN PERFORMANCE LAB EXPERIENCE 4 SUBMAXIMAL AEROBIC TESTING Additional Study Resource ACSM s Guidelines for Exercise Testing and Prescription 7th Ed 2006 The Y s Way to Physical Fitness 1982 Heyward 2006 pp 80 PURPOSE 1 To become familiar with sub maximal exercise testing via two commonly used protocols the YMCA Bicycle Ergometer Protocol and Queens College 3 minute Step Test and to compare predicted estimated VO2max results between and within subjects EQUIPMENT NEEDED 16 25 Bench Step Body weight scale Cycle Ergometer Metronome RPE Scales Stopwatches Polar HR Monitor Blood pressure cuff and stethescope INTRODUCTION Maximal oxygen consumption VO2max is used to evaluate an individual s aerobic capacity and fitness Higher VO2max values are generally associated with greater aerobic fitness There are many methods to estimate VO2max the most accurate being a maximal test However maximal tests are not always the most practical and can be expensive and dangerous for certain populations In these cases or in other cases where a maximal test is not practical submaximal tests are often used The YMCA Bicycle Ergometer Test and the Queens College 3 minute Step Test are two common submaximal protocols Prior to any performing any exercise tests certain precautions must be taken to reduce the risk to clients subjects First there should always be an emergency plan in place and all technicians should be aware of this plan and trained to use it1 In this lab there is an emergency phone available in the laboratory and the instructor is trained in Adult CPR AED and First Aid All potential subjects must first be evaluated for any contraindications to exercise testing A listing of absolute and relative contraindications can be found below in Table 1 from the ACSM Guidelines In addition each member of the class must always be sure to monitor all subjects continuously ask how they are feeling and help them down from any apparatus used in class Additional precautionary measures taken in class include constant monitoring of heart rate HR and blood pressure BP We will use Borg s RPE scale to monitor how subjects are feeling at regular intervals throughout the test Do not forget to monitor the subject during the cool down and recovery period Occasionally cardiovascular complications can occur after exercise so it is essential to continue to ask how subjects are feeling and look for signs of illness ACSM Table 2 Contraindications to Exercise Testing Absolute A recent significant change in the resting ECG suggesting significant ischemia recent myocardial infarction within 2 days or other acute cardiac event Unstable angina Uncontrolled cardiac arrhythmias causing symptoms or hemodynamic compromise Severe symptomatic aortic stenosis Uncontrolled symptomatic heart failure Acute pulmonary embolus or pulmonary infarction Acute myocarditis or pericarditis Suspected or known dissecting aneurysm Acute infections Relative Left main coronary stenosis Moderate stenosis valvular heart disease Electrolyte abnormalities e g hypokalemia hypomagnesemia Severe arterial hypertension i e systolic BP of 200 mmHg and or diastolic BP of 110 mmHg at rest Tachyarrhythmias or Bradyarrhythmias Hypertrophic cardiomyopathy and other forms of outflow tract obstruction Neuromuscular musculoskeletal or rheumatoid disorders that are exacerbated by exercise High degree atrioventricular block Ventricular aneurysm Uncontrolled metabolic disease e g diabetes thyrotoxicosis or myxedema Chronic infections disease e g mononucleosis hepatitis AIDS Relative contraindications can be superseded if benefits outweigh risks of exercise In some instances these individuals can be exercised with caution and or using low level end points especially if they are symptomatic at rest Taken from ACSM s Guidelines for Exercise Testing and Prescription 7th edition General Indications for Stopping an Exercise Test in Low Risk Adults Onset of angina or angina like symptoms Significant drop 20mmHg in systolic blood pressure or a failure of the systolic blood pressure to rise with an increased exercise intensity Excessive rise in blood pressure systolic pressure 260mmHg or diastolic pressure 115mmHg Signs of poor perfusion light headedness confusion ataxia pallor cyanosis nausea or cold and clammy skin Failure of heart rate to increase with increased intensity Noticeable change in heart rhythm Subject requests to stop Physical or verbal manifestations of severe fatigue Failure of the testing equipment Assumes that testing is non diagnostic and is being performed without direct physician involvement or electrocardiographic monitoring For clinical testing other criteria are used Taken from ACSM s Guidelines for Exercise Testing and Prescription 7th edition Participant education is another important factor in ensuring a good safe test For this reason all subjects must be informed of everything that is going on during the test This includes statements such as Ok we re going to increase the resistance a little bit now and continuously communicating with subjects about how they are feeling Before anything is changed during a test subjects must be informed as to what is happening Good communication is critical in any laboratory situation SUBMAXIMAL VS MAXIMAL EXERCISE TESTING Submaximal tests can highly correlate with maximal tests in that they can be used to accurately predict VO2max Submaximal tests make the following assumptions1 A steady state heart rate is obtained for each exercise work rate A linear relationship exists between heart rate and work rate The maximal heart rate for a given age is uniform Mechanical efficiency i e VO2 at a given work rate is the same for everyone Steady state heart rate can be easily evaluated by measuring heart rate during every minute of the test If the heart rate changes by more than 5 bpm during the last minute of a stage the stage is extended until heart rate becomes steady Maximal heart rate is predicted using the 220 age formula Because this is only an estimation based on population norms it is not 100 accurate for every individual Even so it provides a good safe estimation and is useful in club personal training settings or anytime when actual VO2 measurements are not possible LAB GROUP STUDENT ASSIGNMENTS 1 Subjects complete both tests today Queens College Step Test The subject must be able to step at the prescribed frequency for 3 continuous minutes YMCA Bicycle Test The subject must be able to