The electrocardiography shows electrical activity in your heart. It is used to diagnose problems with your heart rate, heart rhythm, diagnose inadequate blood and oxygen supply to the heart. An ECG can provide clues about enlargement of the chambers or walls of the heart, heart defects and other heart problems.
Electrocardiography is the fundamental method for other diagnostic methods in sports medicine, for instance, veloergometry, treadmill testing, complex cardiopulmonary exercise testing, anaerobic testing, calorimetry.