Fitness, childhood IQ may affect old-age brain function

Oct. 9, 2006
Courtesy American Academy of Neurology and World Science staff

How well your mind works in old age de­pends more on your fit­ness than on your IQ as a child, ac­cord­ing to a study in the Oct. 10 is­sue of the re­search jour­nal Neu­rol­o­gy.

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In the re­search, 460 adults took a cog­ni­tive test at age 79 iden­ti­cal to one they had tak­en de­c­ades ago, at age 11, in a study called the Scot­tish Men­tal Sur­vey.

Re­sults showed phys­i­cal fit­ness con­tri­bu­t­ed more than three per­cent of the dif­fer­en­ces in old-age cog­ni­tive abil­i­ty, af­ter ac­count­ing for child­hood test scores, said study au­thor Ian Dea­ry of the Uni­ver­si­ty of Ed­in­burgh in Scot­land.

Fit­ness en­hanced old-age cog­ni­tive abil­i­ty more than child­hood IQ did, he added. “Thus, two peo­ple start­ing out with the same IQ at age 11, the fit­ter per­son at age 79 will, on av­er­age, have bet­ter cog­ni­tive func­tion.”

Fit­ness was de­fined by the time it took to walk six me­ters, grip strength and lung func­tion.

“The oth­er re­mark­a­ble re­sult,” said Dear­y, was that “par­tic­i­pants with a high IQ as a child were more like­ly to have bet­ter lung func­tion at age 79. This could be be­cause peo­ple with higher in­tel­li­gence might re­spond more fa­vor­a­bly to health mes­sages about stay­ing fit.”

Oc­cu­pa­tion and educa­tion were also as­so­ci­at­ed with old-age fit­ness, he added; bet­ter-ed­u­ca­ted peo­ple in more pro­fes­sion­al ca­reers had bet­ter fit­ness and higher men­tal test scores.