Expert's comment following the text makes a few good pertinent points.

It is a fact that sports related activities of all kinds, including treadmill stress test, are known

to rarely trigger cardiac arrests and deaths. Some years ago at LA marathon there were three deaths due to

sudden cardiac arrest. The former Michigan governor, George Romney, died of cardiac arrest 

in his 80's while exercising on his treadmill according to his son who ran for president as his father did.

I was once invited by my patient to play golf at his private club, and while playing 18 holes, my patient

showed spots where so and so, including one of my patients, either died suddenly or had a heart attack while playing golf.

I was once asked to give a talk to a group of doctors on the risk of doing exercise, not the benefit of exercise.

I must tell you that in the early years of so called cardiac rehab for those patients who recently had MIs

the excercise techs or paramedicals who were following the protocol but did not know the extent of the patient's

heart function were unwittingly inducing cardiac arrests once in a while by exercising the patient too much.

All I can say is that once again we have to quote Confucius' advice, moderation 중용 to answer this question.

To me, as a physician, all patients, all of us, including me, appear to be all blind, ignorant or oblivious, in the sense that

we do not know our body, our mind, our heart, etc, and can not see what's coming around the corner.

We can't help it. We are only creations, and our knowledge is limited in spite of everything we have achieved.