INSTRUCTION: Answer questions 51 to 55 in relation to text 1. 

TEXT 1 

An effort to count the world’s sloths

1. A paper in the Lancet, shamelessly timed to coincide
2. with the Olympic games, compares countries’ rates of
3. physical activity. The study it describes, led by Pedro
4. Hallal of the Federal University of Pelotas, in Brazil,
5. is the most complete portrait yet of the world’s busy
6. bees and couch potatoes. It suggests that nearly a
7. third of adults, 31%, are not getting enough exercise.
8. That rates of exercise have declined is hardly a
9. new discovery. Since the beginning of the industrial
10. revolution, technology and economic growth have
11. conspired to create a world in which the flexing of
12. muscles is more and more an option rather than a
13. necessity. But only recently have enough good data
14. been collected from enough places to carry out the
15. sort of analysis Dr Hallal and his colleagues have
16. engaged in.
17. The high rates of inactivity he found in his paper are
18. worrying. Paradoxically, human beings seem to have
19. evolved to benefit from exercise while eschewing it
20. whenever they can. In a state of nature it would be
21. impossible to live a life that did not provide enough of
22. it to be beneficial, while over-exercising would use up
23. scarce calories to little advantage. But that no longer
24. pertains. According to another paper in the Lancet,
25. insufficient activity these days has nearly the same
26. effect on life expectancy as smoking.

The Economist Jul 21st 2012, from the print edition.

O estudo realizado por Pedro Hallal aponta