Is It a Healthy Interest?
The Guinness Book of World Records describes Ranulph Fiennes as the world's greatest living explorer. His journeys include the first polar circumnavigation (极地环行) and the first unsupported crossing of the Antarctic continent on foot. So when he suffered a heart attack, it came as something of a surprise.
Exercise is highly beneficial as it reduces both the pulse (脉搏) rate and the blood pressure so reducing stress on the heart as it brings blood round the body. It also helps to keep the artery (动脉) walls more elastic (有弹性的).
But can you push yourself too much? On the subject of exercise, it is good to take several parts of “moderate” exercise a week，which is a little more than quick walking. “We need to be careful when we're doing extreme sports,” says expert Len Almond. “Extreme stress can make almost impossible demands on the body's ability to recover. The stress of extreme sports forces biochemical changes in the body, and the physical response to that kind of activity will be too extreme.”
We all know how the Olympics began. The man who ran 26 miles from the town of Marathon to Athens with news of a victory died as soon as he arrived，and the cause of his sudden death might be the heart attack. Further research was done by scientists. They studied cyclists (自行车运动员) on a race that covers 230km with a height change of 5,500m. They were interested in one particular enzyme (酶), high concentrations of which are found in those who have suffered a heart attack. The scientists found that levels of this chemical increased in most of the cyclists who completed the race. The largest increases were seen in the fastest cyclists who had trained the hardest.
Most of us will never put our bodies to such extreme sports. But if, when you hear about someone like Fiennes，you ask whether exercise is worth it. I advise you to consider your own condition. Personally, I agree with the saying: “Run not to add years to your life but to add life to your years.”
