Many bike races are difficult because they involve going mostly uphill, making them brutal grinds that tear apart quadriceps.

A race that goes downhill, though, like this one in Valparaiso, Chile, presents a completely different challenge.

Wiping out becomes a brutal, and very real, obstacle. Control is difficult, particularly with the changing terrain and angle of the landscape. And speed, obviously an asset in racing, also poses a huge danger and problem.

Ever tried to ride a bike down stairs? It isn’t easy.