Detecting ECG Daniela Paszkiewicz and Lyndsey Wessel Abnormalities in VO2 Max Tests ECG “An electrocardiogram (ECG) is a medical test that detects cardiac (heart) abnormalities by measuring the electrical activity generated by the heart as it contracts. ” http://www. istockphoto. com/file_thumbview_approve/3733 698/2/istockphoto_3733698-electrocardiogram-ecg-ekgwith-human-heart-on-screen. jpg Function of Electrocardiograph Electrocardiograph measures a patients ECG ECG can help detect a variety of health conditions ECG frequency is calculated using a Fourier series as it is a periodic waveform Measures heart muscle activity by monitoring
ECG Explanation P wave represents atrial depolarisation QRS complex represents ventricular depolarisation T wave represents the rapid repolarisation of the ventricles. http://content. answers. com/main/content/img/oxford /Oxford_Sports/0199210896. electrocardiogram. 1. jp g Frequency = 1. 17Hz ECG Trace of Normal, Healthy Heart http://www. vanth. org/vibes/images/normalECG2. PNG ECG Trace of Irregular, Unhealthy Heart http://www. yourdoctor. net/images/cardiovascular/MI/MI_ECG_changes. jpg Application of Electrocardiograph Electrodes are attached to a persons chest, arms and legs using suction cups or sticky gel.
The electrodes detect the electrical currents generated by the heart. After all procedures, electrodes are removed and results are analyzed immediately. VO2 Max “the highest rate of oxygen consumption attainable during maximal or exhaustive exercise” http://www. sport-fitness-advisor. com/images/vo2max_graph. jpg Function of VO2 Max Test Considered best indicator of cardio respiratory endurance and aerobic fitness VO2 max is expressed relative to body weight VO2 Max tests measure; Max O2 uptake, aerobic power and aerobic http://www. bc. ca/canada/britishcolumbia/features/athletesblog/image s/treadmill. jpg Equipment Required: – Application of VO2 Max Test Oxygen and Carbon Dioxide analysers – Ergometer – Douglas Bag or Tissot Tank – Pneumotach or Turbine Ventilator Procedure: Application of VO2 Max Test Exercise is performed on appropriate ergometer ( treadmill, cycle, swim bench) Exercise workloads are selected to gradually progress in 1. 2. Application of VO2 Max Test Scoring of VO2 Max Tests: –
Results are shown in either L/min (liters per minute) or ml/kg/min (mls of O2 per kilogram of body weight per minute) VO2 max is reached when the following occur; Plateau of O2 uptake Max HR is reached Respiratory exchange ratio of 1:15 or greater Volitional Exhaustion – Relevance of ECG and VO2 Max Test ECG – ECG testing determines whether heart problems or abnormalities exist, and this can then aid in writing specialised training programs. Knowing whether heart abnormalities or problems exist also allows sports scientists and exercise scientists to be aware of limitations of athletes or patients. VO2 Max Test – VO2 max scores can be used to give an indication of CV endurance and aerobic capacity, and can be used by Sports Scientists when working with elite ECG and VO2 Max Tests Exercise testing: – – elicits body’s reaction to acute exercise. Changes in HR, BP and Respiration rate can help provide a quantitative estimation of cardiovascular conditioning and function. Heart abnormalities not present at rest, can be detected during exercise. PR-Segment: – – Normal ECG Responses During Exercise Shortens Sloped downwards S-Wave: – – – Normal ECG Responses During Exercise
Greater in depth Greater deflection at max exercise Returns to resting values gradually during recovery Normal ECG Responses During ST-Segment: Exercise Shifts right – – Shifts up Normal ECG Responses During T-Wave: Exercise Amplitude decreases at first – – – Amplitude increases at max exercise At 1min into recovery, amplitude is equal to resting values Normal ECG Responses During P-Wave: Exercise Becomes more vertical – – Magnitude increases Abnormal ECG Responses During Exercise, and What R-Wave: They Indicate Amplitude increase; cardiac disease –
Abnormal ECG Responses During Exercise, and U-Wave: What myocardial ischemia, left anterior They Indicate Inversion; – descending coronary artery disease (CAD) – – Abnormalities may be hard to asses due to size U-wave is not very easily visible Abnormal ECG Responses During Exercise, and What ST-Segment: They Indicate – – – Depression; exercise induced myocardial ischemia Elevation; previous myocardial infarction Elevation and Depression in same test; multivessel coronary artery disease (CAD) Elevation in patients who have not had previous myocardial infarction: severe transient ischemia Appendices: Ambulatory ECG – – Application of Electrocardiograph Involves a patient wearing a device for at least 24hrs Can detect symptoms not seen in resting ECG Cardiac Stress Test – Analyses heart function of patient during exercise Recording lasts approximately 15-30mins – Relevance of VO2 Max test and ECG Sports Science: Our Bachelor of Sports Science prepares you to clearly understand the process by which high performance athletes achieve greater results, while providing you with a solid understanding of the basic, clinical and applied sciences.
Exercise Science: ECG in VO2 Max Test Procedure 1. Patients are instructed not to eat or smoke for 23 hrs prior to exercise testing. They are also informed not to participate in any strenuous physical efforts 12hrs before testing, and to cease taking medications, as some may interfere with exercise responses. 2. A brief medical history is undertaken, and any previous conditions are noted. Patients with previously diagnosed angina, uncontrolled heart failure or adults with severe aortic stenosis should