This just in: sitting on a giant exercise ball during your 12-hour workday isn’t better than sitting on a regular old chair. Researchers at the University of Waterloo in Ontario had sprightly, young volunteers sit alternately on a ball, an office chair, and a backless stool while machines measured muscle activity in their core and lower backs and found no significant differences. They don’t improve posture or reduce back pain, and they don’t give you abs of steel. So do they serve any purpose other than making you look foolish? One 2008 study found workers burned roughly four more calories per hour on ball chairs, but they were also more likely to fall over while reaching for the stapler, hence the foolishness.