#21: Nope!
Mixing hilarious performances with over-the-top costumes is a staple of synchronized swimming, but these competitors are no joke. An aerobics test run before the 2012 London games showed that synchronized swimmers were second in athletics only to long-distance runners. They can hold their breath for up to two minutes underwater!
They use nose plugs to keep their sinuses from being affected by long-term water damage, as they often spend much of their performances upside down underwater. This is a woman-only Olympic sport, but many men compete at national levels and hope to get into the Olympic scene soon.