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Set Your Body’s Time Clock
Our Body Operates Like a Clock As the first rays of sunlight filter over the hills of California’s Silicon Valley, Charles Winget opens his eyes. It is barely 5 a.m., but Winget is raring (渴望) to go. Meanwhile, his wife pulls up the covers and buries her face under,the pillow. "For the past fifteen years," says Winget, "We’ve hardly ever gotten up together."
The Wingets’ situation is not uncommon. Our bodies operate with the complexity of clocks, and like clocks, we all run at slightly different speeds. Winget is a morning person. His wife is not at her best until after nightfall.
Behavioral scientists long attributed such differences to personal eccentricities or early conditioning. This thinking was challenged in the late 1950s by a theory labeled chronobiology by physician-biologist Franz Halberg. In a Harvard University laboratory, Dr. Halberg found that certain blood cells va
A. heart rate kept steady all day
B. we could attain peak efficiency at a certain time each day
C. human body functioned at an unchanging rate
D. body temperature had no changes all day