阅读下而短文，从短文后的选项中选出可以填入空白处的最佳选项。选项中有两项为多余选项。
When it comes to exercise ,do you swear by working up a sweat with a good run,or do you prefer to take a walk? It turns out both runners and walkers get health benefits compared with couch potatoes. But is one really better than the other for fitness? 16
It's always good to get any kind of exercise and it's important that you choose exercise that you can do regularly. 17 For instance，running for half an hour burns about twice the calories as a half-hour of walking. But if the walker covers the same distance,just over a longer period of time ,he/she will burn the same calories.
What about other health benefits? Running and walking are both excellent for heart health. When you run. your heart works harder than when you walk. 18 If runners and walkers burn the same number of calories every day，both groups have a lower risk of heart disease than inactive people.
19 For instance, running or walking at least 30 minutes a day may help lessen mild bone loss. And contrary to what you may think,runners don't suffer from arthritis(关节炎) more than non-runners.In fact,their risk for arthritis is about 15% lower than for those who don't exercise at all.
You don't have to feel torn between running and walking. 20
A.Most people will say “yes” to this question.
B. Both types of exercise are also good for bone health.
C.It doesn't matter if you run or walk as long as you keep moving.
D. Let's first take a look at the health benefits of running and walking.
E. But that doesn't actually mean that runners have better heart health than walkers.
F. One large study found runners might have a lower chance of getting heart disease.
G. The main difference between walking and running is that running burns calories faster.
参考答案
16-20 DGEBC
