Most of us use alarm clocks to wake up at the right time for school or work. We look at our watches to know the right time for the bus or train. However, there is also a right time to eat, sleep, exercise, and take medicine, too. We can’t look at a clock for the right time for these activities. We must listen to the clock inside our bodies: the biological clock.

Barbara Wells exercised every morning. She woke up at 6:00 am. She ran about two miles before she went to work. But Barbara’s legs and back started to hurt. She did some exercises before she ran. But her legs and back still hurt. She ran slower, but the pain didn’t stop. Barbara talked to her doctor. The doctor said, “Don’t run in the morning. Try to exercise later in the day. That is the time when your body is at the right temperature for exercises after work.” Her legs and back don’t hurt anymore.

Today, doctors are learning more about chronobiology (时间生物学), the study of biology clocks. They are learning about the importance of time for our bodies. For example, it is best for people to go to sleep at the same time every night and to eat only when they’re hungry. Also, doctors discovered that some illness, such as heart attacks(心脏病), occur(发生)most often in the morning. This information tells them that the best time to take heart medication may be at night. When patients take heart medicine at night, they may prevent a heart attack in the morning.

Many doctors believe chronobiology can help us live healthier lives. It may be the right time to listen to these doctors!

35. Do we all have a biological clock inside our bodies?

36 How far did Barbara Wells run every morning?

37. How did Barbara’ legs and back get well?

38. What is the right time for a heart attack person to take heart medicine?

39. What can we learn from the passage?