science of us

Doing Yoga at Work Is Even Dumber Than You Thought

Photo: Paul Bradbury/Getty Images

Workplace wellness programs — an umbrella term for a number of potential health-related employer offerings, like free in-office yoga classes, health screenings, weight-loss incentives, and gym membership discounts — have become increasingly popular in the last ten years, thanks in large part to these programs’ reported success. A 2010 meta-analysis, for instance, indicated that companies’ medical spending decreased in direct proportion to wellness program spending, as did the number of sick days taken by employees. Findings like these have contributed to the inflation of the workplace wellness market, said to be valued at eight billion dollars in the U.S. alone. But most (if not all) of the prior research on the topic has relied on self-selecting data points, evaluating the programs’ effect on employees who volunteer to participate in such programs, who may be likely to differ substantially in personality and lifestyle from those employees who abstain.

A truly telling study on workplace wellness programs would require randomization and a control group, which is what a group of researchers set out to do with a large employer based in Illinois, for a study published in the National Bureau of Economic Research. At an office with more than 12,000 employees, the researchers designed a workplace wellness program that included screenings, smoking cessation and weight-loss programs, and Tai Chi sessions. Five thousand of those employees expressed an interest in the wellness program. A third of these were then randomly assigned to the control group and left to participate (or not) as they chose. The remaining two thirds, the experimental group, were given screenings and risk assessments, and encouraged to attend available wellness activities over the following year. Using this design, researchers were better able to control for those individual factors which might affect the success of a particular employer’s wellness programs.

Unfortunately for those employers spending exorbitant amounts of money on programs like these, the study’s authors found that they made little to no impact on employee health. One of the primary motivators for employers in creating wellness programs is their supposed impact on sick-day reduction (worker illness and injury cost U.S. employers more than 225 billion per year), but the employees who took part in the study’s program didn’t take significantly fewer sick days than their counterparts, and their medication and hospital spending were roughly the same. Nor were the wellness program participants any more likely to start using the gym any more frequently. They were also, notably, no less likely to leave their jobs than those who didn’t participate, which suggests these programs don’t do much for morale, either.

The study’s authors say these findings suggest that previous studies on workplace wellness programs relied too heavily on self-selection, which drastically narrowed the diversity of their samples. People who participate in workplace wellness programs tend to be younger, in better health, and better off financially than those who don’t — people who, researchers argue, would likely have had better health outcomes regardless. Employers hoping to reduce employee sick days (and improve employee health) might do better to spend that extra money on, say, better health coverage. Just one idea.

Doing Yoga at Work Is Even Dumber Than You Thought