22 / 44

Japanese gymnast Kazuhito Tanaka

Japanese gymnast Kazuhito Tanaka slips while performing on the horizontal bar during the Artistic Gymnastics men's qualification at the 2012 Summer Olympics, Saturday, July 28, 2012, in London. (AP Photo/Gregory Bull)

Olympic bloopers

Whether it's due to human error or plain old gravity, things don't always go as planned at the Olympics.