A 700-foot span across a deep canyon gorge.

Beam bridges typically span up to 250 feet, and they're also the cheapest and easiest bridges to build. Congrats -- you've just made a lot of rollerbladers and bikers very happy!

While maintaining this bridge position, lift your right foot a few inches off the floor ... who really struggle with this," Roberts says. Build up to doing it by dialing back: Simply lift and ...