I think there was a science experiments book for kids that dared me to drink water from a glass upside down through a straw while hanging from monkey bars or something. It was meant to show how our body deliberately moves food towards the stomach instead of solely relying on gravity, but instead it showed that I my legs were too weak.

A shame these experiments are deemed to dangerous nowadays and people have to show their ignorance online, simply because the new metal straws have pierced the brains of anyone who did them.