2 . Running is often tiring and a lot of hard work, but nothing beats the feeling you get after finishing a long workout around the track. But while it’s long been believed that endorphins (脑内啡), chemicals in the body that cause happiness, which are behind the so-called runner's high, a study suggested that there may be more to this phenomenon (现象) than we previously knew.
According to a recent study published by a group of scientists from several German universities, a group of chemicals called endocannabinoids (内源性大麻素) may actually be responsible for this familiar great feeling.
To test this theory, the scientists turned to mice. Both mice and humans release high levels of endorphins and endocannabinoids after exercise, along with many other chemicals. After exercising on running wheels, the mice seemed happy and relaxed and displayed no signs of anxiety. But after being given a drug to block their endorphins, the mice’s behavior didn't seem to change. However, when their endocannabinoids were blocked with a different drug, their runner's high symptoms (症状) seemed to fade.
“The long-held notion of endorphins being responsible for the runner’s high is false. Endorphins are effective pain relievers, but only when it comes to the pain in your body and muscles you feel after working out,” Patrick Lucas Austin wrote on science blog Lifehacker.
Similar studies are yet to be carried out on humans, but it’s already well known that exercise is a highly effective way to get rid of stress or anxiety. The UK's National Health Service even prescribe (开药方) exercise to patients who are suffering from depression. “Being depressed can leave you feeling low in energy, which might put you off being more active. Regular exercise can boost your mood if you have depression, and it’s especially useful for people with mild to moderate depression,” it wrote on its website.
It seems like nothing can beat that feeling we get after a good workout, even if we don’t fully understand where it comes from. At least if we're feeling down, we know that all we have to do is put on our running shoes.
1. What did scientists from Germany universities recently discover?
| A．Endorphins may contribute to one’s high spirits after running. |
| B．The runners’ high could be caused by endocannabinoids. |
| C．The level of endorphins and endocannabinoids could affect one's mood. |
| D．Working out is a highly effective way to treat depression. |
2. Why did scientists give mice drugs in their experiment?
| A．To test what influences the level of endocannabinoids released. |
| B．To see the specific symptoms of the runner's high. |
| C．To identify what is responsible for the runner’s high. |
| D．To find what reduces the runner's high symptoms. |
3. What does the underlined word “notion” probably mean in Paragraph 4?
| A．belief. | B．activity. | C．effect. | D．question. |
4. What can we learn according to the UK’s National Health Service?
| A．Workouts can help people completely recover from depression. |
| B．Workouts are the best way to treat depression. |
| C．Workouts only work for those with depression. |
| D．Workouts can help ease depression symptoms. |
