题目内容：

    Runners need to move 15 per cent faster on a treadmill(跑步机) to burn the same number of calories as jogging outdoors, research reveals.

Researchers from Milan University analyzed the difference between running outdoors and on a treadmill in 15 physically fit males with an average age of 21. The participants completed a sprint(短距离快速跑) for 30 seconds followed by 30 seconds of recovery for a total of 15 minutes both outdoors and on a treadmill. Oxygen use and exercise intensity were measured after both types of running.

The findings were published in the journal of Applied Physiology, Nutrition and Metabolism. Results revealed that when on a treadmill, runners use significantly lower amounts of oxygen, suggesting less effort is required. Therefore runners must move 15 percent faster on a treadmill to burn the same amount of calories as exercising outdoors, the study stated. The study authors wrote, "A 15 per cent increase in running speed during a period of stopping and starting often in high intensity treadmill training session is the best possible solution to reaching the same physiological responses as an outdoor training session.

Although the study did not speculate why treadmill running appears to be needing less effort and energy, previous research suggests the moving belt of a treadmill moves joggers forward, causing them to move faster. Exercising indoors also means gym-goers do not have to fight with steep hills or wind resistance.

Michael Silverman, director of rehabilitation and wellness(康复科) at Northern Westchester Hospital in New York, said, “Outdoors, you are changing surfaces constantly, fighting the wind, and making quick and sudden starts and stops, which will lead to increased caloric burn.” Shake magazine reported. "And while we don't recommend running in extreme temperatures, it is worth noting that your body burns extra calories to regulate your body temperature," he says.

1.Where can you find the specific findings of the study?

A.In Paragraph 2 B.In Paragraph 3 C.In Paragraph 4 D.In Paragraph 5

2.What can we know about the study?

A.Its participants were all 21 years old .

B.Michael is one of the researchers.

C.It revealed why treadmill running consumes less calories .

D.It took oxygen use and exercise intensity into consideration .

3.Why does running on a treadmill seem easier according to the study ?

A.The runners need less energy.

B.The runners can usually get enough oxygen .

C.The moving belt pushes joggers forward .

D.The intensity of running on the treadmill is more stable .

4.What does the underlined word “speculate” mean ?

A.conclude B.research C.oppose D.doubt