Captivating photo shows Simone Biles' amazing concentration while flipping upside down over the four-inch wide balance beam

Of all of the gravity-defying stunts gymnasts pull, their seemingly impossible moves on the four-inch wide balance beam are particularly daunting.

Lest anyone think it's easy, flipping upside down on the beam is not only athletically challenging, it requires intense concentration.

During the women's gymnastics finals, a snapshot of Simone Biles in mid-flip, staring intensely at the beam while hovering just inches above it, proves how ridiculous these athletes are.

Look at that concentration!

Aerial photos of the beam show small gymnasts' margin for error is.

Do not try this at home.

NOW WATCH: Here's what Rio's 'uninhabitable' Olympic Village looks like

Please enable Javascript to watch this video