Tuesday, March 20, 2018

Being what we think we are.

Gretchen Reynolds points to an interesting article in Health Psychology by Zahrt and Crum. Following up on an earlier article in which
Crum and her co-author studied 84 female hotel-room attendants, who told the researchers that they felt they completed little or no daily exercise, although their work consisted mostly of physical labor. Crum and her colleague explained to half of them that, in fact, they were meeting or exceeding national recommendations for 30 minutes of daily exercise; a month later, when the researchers checked back, the women said they believed they were getting more exercise than before. They had lost weight and body fat and developed lower blood pressure. But in fact, their daily exertions were the same.
Their new study examined information from 61,141 participants who answered questions about whether they felt they were getting more, less or about the same amount of exercise as most people their age.
They found a strong correlation between people’s dying early and their believing that they were relatively inactive, even if their accelerometer data indicated that they were getting as much exercise as others their age in this group. Risk of early death was up to 71 percent higher than for the group that, correctly or not, felt confident that they exercised more than their peers. This correlation held true when the researchers controlled for chronic diseases, socioeconomic status, smoking and other factors.
Another article, by Paula Span, reports work by Levy et al. extending studies that have shown that people with more positive self-perception of aging actually live longer by an average of 7.5 years. The more recent study shows that implicit interventions can work subliminally to strengthen older people’s positive age stereotypes. That leads, in turn, to stronger physical functioning. The effects were still evident three weeks after the intervention ended. Here is the abstract from Levy et al.:
Negative age stereotypes that older individuals assimilate from their culture predict detrimental outcomes, including worse physical function. We examined, for the first time, whether positive age stereotypes, presented subliminally across multiple sessions in the community, would lead to improved outcomes. Each of 100 older individuals (age = 61–99 years, M = 81) was randomly assigned to an implicit-positive-age-stereotype-intervention group, an explicit-positive-age-stereotype-intervention group, a combined implicit- and explicit-positive-age-stereotype-intervention group, or a control group. Interventions occurred at four 1-week intervals. The implicit intervention strengthened positive age stereotypes, which strengthened positive self-perceptions of aging, which, in turn, improved physical function. The improvement in these outcomes continued for 3 weeks after the last intervention session. Further, negative age stereotypes and negative self-perceptions of aging were weakened. For all outcomes, the implicit intervention’s impact was greater than the explicit intervention’s impact. The physical-function effect of the implicit intervention surpassed a previous study’s 6-month-exercise-intervention’s effect with participants of similar ages. The current study’s findings demonstrate the potential of directing implicit processes toward physical-function enhancement over time.


  1. Do you think studies 1 and 3 would replicate?
    For the 2nd study - seems like the question how fit are u relative to others would correlate highly with question about activity. No surprise that people who think they are less fit have higher risk of dying. (They controlled for chronic disease but how about BMI, cholesterol, glucose, blood pressure etc. — my guess is there is underling difference in health in those who say they are inactive)

  2. 1 and 3 should be taken with grain of salt until replicated, good point on 2.