Mind-set matters -- Why thinking you got a work out may actually make you healthier

February 6, 2007

As the commitment to our New Year's resolutions wanes and the trips to the gym become more infrequent, new findings appearing in the February issue of Psychological Science may offer us one more chance to reap the benefits of exercise through our daily routine. Harvard University psychologist Ellen Langer and her student Alia Crum found that many of the beneficial results of exercise are due to the placebo effect.

The surgeon general recommends 30 minutes of daily exercise to maintain a healthy lifestyle. While this may be harder for those who are required to sit behind a desk for eight hours, other jobs are inherently physical, like a hotel housekeeper. On average, they clean 15 rooms per day, each taking 20 to 30 minutes to complete. According to the study, the housekeepers might not perceive their job as exercise, but if their mind-set is shifted so that they become aware of the exercise they are getting, then health improvements would be expected to follow.

The researchers studied 84 female housekeepers from seven hotels. Women in 4 hotels were told that their regular work was enough exercise to meet the requirements for a healthy, active lifestyle, whereas the women in the other three hotels were told nothing. To determine if the placebo effect plays a role in the benefits of exercise, the researchers investigated whether subjects' mind-set (in this case, their perceived levels of exercise) could inhibit or enhance the health benefits of exercise independent of any actual exercise.

Four weeks later, the researchers returned to assess any changes in the women's health. They found that the women in the informed group had lost an average of 2 pounds, lowered their blood pressure by almost 10 percent, and were significantly healthier as measured by body-fat percentage, body mass index, and waist-to-hip ratio. These changes were significantly higher than those reported in the control group and were especially remarkable given the time period of only four weeks.

Langer writes, "Whether the change in physiological health was brought about directly or indirectly, it is clear that health is significantly affected by mind-set." This research shows the moderating role of mind-set and its ability to enhance health, which may have particular relevance for treating diseases associated with a sedentary lifestyle.

Source: Association for Psychological Science