Can exercise be a bad thing? Sudden death during or soon alter strenuous exertion on the s
Most cases of sudden death in sport are caused by lethal arrhythmias in the beating of the heart, often in people【51】undiagnosed coronary heart disease. In North America【52】over 35 is advised to have a physical check-up and even an exercise electrocardiogram. The British, on the whole, think all this testing is unnecessary. Not many people die from exercise,【53】, and ECGs (心电图) are notoriously inaccurate. However, two medical cardiologists at the Victoria Infirmary in Glasgow, advocate screening by exercise ECG for people over 40, or younger people【54】at risk of developing coronary heart disease. Individuals showing a particular abnormality in their ECGs【55】, they say, a 10 to 20 times greater risk of subsequently developing signs of coronary heart disease, or of sudden death.
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A.Then
B.Though
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