根据以下材料，回答题 Young Adults Who Exercise Get Higher IQ Scores Young adults who are fit， have a higher IQ and are more likely to go on to university， reveals a major new study __________ （51） out at the Sahlgrenska Academy and Sahlgrenska University Hospital. The results were recently published in the Proceedings of the National Academy of Sciences （PNAS）. The study __________ （52） 1.2 million Swedish men doing military service who were born between 1950 and 1976. The research group analyses the __________ （53） of both physical and IQ tests the youngsters took right after they started serving the army. The study shows a clear link __________ （54） good physical fitness and better results for the IQ test. The strongest links are for __________ （55） thinking and verbal comprehension. But it is only fitness that plays a __________ （56） in the results for the IQ test， and not strength. 'Being fit means that you also have good heart and lung __________ （57） and that your brain gets plenty of oxygen，' says Michael Nilsson， professor at the Sahlgrenska Academy and chief physician at the Sahlgrenska University Hospital. 'This may be one of the reasons why we can see a clear link with fitness， but not with muscular __________ （58）. We are also seeing that there are growth factors that are important.' By analyzing data for twins， the researchers have been __________ （59） to determine that it is primarily environmental factors and not genes that __________ （60） the link between fitness and a higher IQ. 'We have also shown that those youngsters who __________ （61） their physical fitness between the ages of 15 and 18 increase their cognitive performance，' says Maria Aberg，researcher at the Sahlgrenska Academy and physician at Aby health centre. 'This being the case，physical education is a __________ （62） that has an important place in schools， and is an absolute must __________ （63） we want to do well in maths and other theoretical subjects.' The researchers have also compared the results from fitness tests during national service__________ （64） the socio-economic status of the men later in life. Those who were fit at 18 were more __________ （65） to go into higher education， and many secured more qualified jobs. 回答（51）题 查看材料