Doctors warn that exercising, especially moderate to severe exercise without knowing any underlying cardiac condition is not good. Dr. Sanjay Mittal Director Clinical and Preventive Cardiology, Heart Institute, Medanta explains, “Every medicine is a poison if given at the wrong time and wrong dose, same is the case with exercise. Certain exercises in a normal person also can increase the risk of certain abnormalities. It can prove to be fatal at times. Hence, it is important to get yourself evaluated before you take up heavy exercising. There are certain categories of people for whom exercising can precipitate heart attacks. narrowing of aortic valve, if there are anomalies of heart circulation that means arteries of the heart are arising from wrong sinuses; electric irregularities of the heart can predispose a person to collapse after exercising. It's best to get yourself evaluated before you take up heavy exercise. The issue of non-detection of heart ailments is a very serious one.

If a person feels dizzy or light headed while exercising, you need to first get yourself evaluated.

If you are hypertensive (extreme hypertension), it is important to control your BP and then exercise . If you have a family history of a young person who had suddenly collapsed without warning, you may be carrying a gene which predisposes you to certain collapse so get ECG done
If you have chest discomfort, undue breathlessness, get yourself evaluated

Performance enhancing drugs can lead to cardiac irregularities and collapse and even heart attack.

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