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We all know that running a few kilometers each day is good for our
health. But what we don't know is that running too much can be bad for us.
A study from the Minneapolis Heart Institute Foundation suggests
that running long distances regularly for many years can make our life shorter
instead of longer. The scientist Dr. James O'Keefe said running too much could
cause plaque (斑) in our heart. This could lead to heart
disease(心脏病). He told that running too much for many
years took away the good things from exercise. He added that the risk of
long-distance runners dying of heart disease could be the same as those who
never exercised.
The study studied 3, 300 runners with an average age of 46. It
showed that 70 percent of the runners ran more than 30 kilometers a week. The
study found that people who were marathon runners for 25 years had 62percent
more plaque in their heart than those of the same age who exercised little or
didn't exercise.
John Hagan, a doctor and long-time runner, said he felt cheated. He
had run marathons since 1967. He used to run up to 60 kilometers every week. He
said, "As a doctor and runner, I felt sorry because I always thought my
heart was very strong. However, I have heart problems now. I advise people to
exercise regularly but not too much. "
