题目内容：

Running a few kilometers each day is good for our health. However, new research says running too much could be bad for us. Running long distances 1. (regular) for many years could make our life 2. (short), not longer. The study is from the Minneapolis Heart Institute. A researcher said too much running can created plague(斑) inside your heart, 3. can lead to heart disease. He wrote that running too much for many years takes away the good things from exercise. He 4. (add) that the risk of heart disease could be 5. same as someone who never exercised.

Researchers looked 6. the health and training of 3,300 runners over the age of 35. 70% of them ran over 30 kilometers a week. Men who ran marathons for 25 years had 62% more plaque in their heart than men who did little 7. no exercise. Another doctor said he felt cheated. He started running marathons in 1967. He used 8. (run) 60 kilometers every week. He said, “I thought I was out there exhausting 9. (me), building an absolutely strong heart.” The doctor advised 10. (exercise) frequently but not to overdo things.