Electrocardiography (ECG) can be applied using different methods. The main types of ECG are:
1. Resting ECG: Standard ECG that measures the heart's electrical activity while at rest.
2. Holter ECG: An ECG performed with a portable device used for continuous monitoring of the heart rhythm over an extended period, such as 24-48 hours.
3. Stress ECG (Exercise Test/Treadmill Test): An ECG that evaluates how the heart responds during physical activity (exercise). This test is particularly used to assess heart performance in conditions like coronary artery disease.