When it comes to walking off those excesses(过剩) , a lengthy hike once a day will do you far more good than nipping down to (一溜烟跑) the shops every couple of hours even if the short walks add up to the

same amount of time, say exercise researchers in Britain. But walks of any length beat sitting at home with your feet up and watching television. They stress. Some researchers in Britain reached these conclusions after putting 56 couch potatoes through an 18 week course of daily walks. They found that longer walks produce the most beneficial changes to the composition of blood fats, but walks of any length improve the fitness of the heart.

In the study, the normally inactive subjects were divided into three roughly equal groups. The "long walker" took a hike of between 20 and 40 minutes every day. "Intermediate walkers" had two rounds of jogging of 10 to 15 minutes, and "short walkers" did three stints of 90 to 110 minutes. The controls sat at home, as usual.

At the start and end of the 18 weeks, the health and fitness of each group were measured and it was found that the long walkers were healthiest, as measured by altered fat profiles in their blood. At the end, each liter of blood from the long walkers contained an average 0.05 grains less apolipoprotein(阿朴脂蛋白) II, a "bad" fat that is linked with heart disease. This was more than twice the drop seen in the intermediate walkers, and five times that in short walkers. In the controls, the level of this fat stayed the same. The drop in apolipoprotein II in the long walker was matched by a rise in the blood level of apolipoprotein I, a "good" fat that is associated with smooth arteries.

1、According to the researchers, ______ is least beneficial to your health.

A、taking a lengthy hike once a day

B、going shopping several times every day

C、doing jogging every morning

D、sitting in the sofa watching TV every evening

2、"Couch potato" in paragraph 2 is used to refer to a kind of ______.

A、farmers

B、vegetables

C、movie-goers

D、TV viewers

3、Which of the following statement is FALSE？()

A、Longer walks benefit our composition of blood fats

B、The subjects in the study all often watch TV

C、Only longer walks benefit our health

D、The subjects in the study may not like exercises

4、The subjects are divided into ______ groups.

A、four

B、three

C、two

D、one

5、Why is long walk beneficial to our heart？()

A、It leads to the drop in apolipoprotein I

B、It leads to the drop in apolipoprotein II

C、It keeps us from watching TV

D、It helps us lose weight