Can the placebo effect work with exer­cise and fit­ness? Two Har­vard psy­chol­o­gists decided to find out, and the results were startling.

84 maids at seven care­fully matched hotels [were quizzed on] how much exer­cise they got. Fully a third of the women said they got no exer­cise at all, while two-thirds said they did not work out reg­u­larly. Langer and Crum took sev­eral mea­sures of the women’s basic fit­ness lev­els, which indi­cated that they, indeed, had the poor health of basi­cally seden­tary peo­ple. Then just over half the women were told an unfa­mil­iar truth: clean­ing 15 rooms daily — push­ing recal­ci­trant vac­uum clean­ers, scrub­bing tubs, pulling sheets — con­sti­tutes more than enough activ­ity to meet the sur­geon general’s rec­om­men­da­tion of a half-hour of phys­i­cal activ­ity daily. [The] con­trol group was left in the dark.

A month later, Langer and Crum checked back with the women to find, as they reported in the Feb­ru­ary issue of Psy­cho­log­i­cal Sci­ence, remark­able results. The aver­age study-group maid had lost 2 pounds, while her sys­tolic blood pres­sure had dropped by 10 points; by all mea­sures the 44 women “were sig­nif­i­cantly health­ier.” Yet there were no reported changes in behav­ior, only in mind-set.

The accom­pa­ny­ing graphic high­lights the find­ings, and the story was also cov­ered by Ben Goldacre in his Guardian col­umn, Bad Sci­ence.

via MeFi