It turns out that sitting an an exercise ball instead of an office chair has no real health benefits, doesn't improve your posture, and doesn't work your core. Basically, you look like a tool for nothing.
According to Jack P. Callaghan, who holds the Canada Research Chair in Spine Biomechanics and Injury Prevention at the University of Waterloo in Ontario, there isn't an advantage to sitting on an exercise ball while you work at your desk. He and his colleagues performed an experiment in which they had volunteers sit on a ball, an office chair, and a backless stool "while machines measured muscle activity in their abdomens and lower backs." The found that there was no difference in the seats and that the ball did not provide any kind of real work out.
Additional research shows that sitting on balls (heh) can actually increase butt pain.
…[I]n part because sitting on a ball chair involves more contact area between the seating surface and your backside than a chair does — you sink into the ball somewhat — many new adopters of ball chairs report increased discomfort in their backsides.
But the good news is that people who sit on exercise balls while working burn off a whopping extra four calories an hour. (You can burn more than that giggling.)
Image via dean bertoncelj/Shutterstock
Ask Well: Ball Chairs [NYT]