In a study published in the British Journal of Sports Medicine, the researchers say that 11 minutes a day (75 minutes a week) of moderate-intensity(强度) physical activity—such as fast walking—would be sufficient to lower the risk of diseases such as heart disease, stroke and a number of cancers.

To explore the amount of physical activity necessary to have a beneficial impact on several chronic(慢性的) diseases and early death, researchers carried out a systematic review, collecting and analysing data from all of the published evidence. In total, they looked at results reported in 196 peer-reviewed articles, covering more than 30 million participants from 94 large study teams, to produce the largest analysis to date of the association between physical activity levels and risk of heart disease, cancer, and early death.

The researchers calculated that if everyone in the studies had done at least 150 min per week of moderate-intensity activity, around one in six (16%) early deaths would be prevented. One in nine (11%) cases of cardiovascular(心血管的) disease and one in twenty (5%) cases of cancer would be prevented.

However, even if everyone managed at least 75 min per week of moderate-intensity physical activity, around one in ten (10%) early deaths would be prevented. One in twenty (5%) cases of cardiovascular disease and nearly one in thirty (3%) cases of cancer would be prevented.

Dr Soren Brage from the MRC Epidemiology Unit said: “If you are someone who finds the idea of 150 minutes of moderate-intensity physical activity a week a bit daunting, then our findings should be good news. Doing some physical activity is better than doing none. This is also a good starting position—if you find that 75 minutes a week is manageable, then you could try stepping it up gradually to the full recommended amount.”

1.What can we know about the study?

A It’s to find out the beneficial impact of exercise.

B More than 30 million people were asked.

C Researchers worked with other 94 teams.

D Researchers studied previous research.

解析：选D。D细节理解题。根据第二段的“researchers carried out a systematic review, collecting and analysing data from all of the published evidence”可知，研究人员们系统回顾了之前的相关研究。故选D。

2.About 21 min a day of moderate-intensity physical activity would prevent _________.

A one in ten cases of cardiovascular disease

B one in thirty cases of heart disease

C nearly one in nine early deaths

D one in twenty cases of cancer

解析：选D。D细节理解题。根据第三段可知，每周150分钟，即每天约21分钟的中等强度活动，可以避免大约六分之一的早死、九分之一的心血管疾病和二十分之一的癌症。故选D。

3.What does the underlined word “daunting” mean?

A Discouraging.

B Humorous.

C Effortless.

D Helpful.

解析：选A。A词义猜测题。根据前文“150 minutes”和后文“then our findings should be good news.”“75 minutes a week is manageable”可知，此处指的是如果一周150分钟的锻炼强度“使人感到气馁”，那么可以从一周75分钟的锻炼开始。故选A。

4.What might Dr Soren Brage agree?

A Regular exercise is recommended.

B 15 minutes of daily exercise is the best.

C Drink a half cup of tea every 15 minutes.

D Increase the amount of exercise step by step.

解析：选D。D推理判断题。根据最后一段最后一句“you could try stepping it up gradually to the full recommended amount”可知，Soren Brage博士建议锻炼时间要循序渐进。故选D。