In some ways, wheelchair racing is closer kin to track cycling than track and field: human-powered locomotion on wheels.

But while it is the rippling leg muscles that define cyclists, wheelchair racers like Toronto's Paralympic champion Jeff Adams have massive, powerful upper bodies that propel their stylized wheelchairs, which have two big back wheels and a single, small front wheel which racers use to do their steering.

The straight sections of the races are spectacles of sheer power, but a good deal of skill and savvy come into play on turns and when racers attempt to overtake opponents, or move to the inside or outside. They have to balance the demands of manual steering controls with raw pushing power and avoid getting tangled up with other wheelchairs. Still, crashes and pileups are a common sight, owing to the speed and intensely competitive atmosphere of the races.

Amputee sprinters, meanwhile, conduct their races just like their able-bodies counterparts, finding the stride that is both the fastest and most comfortable with their prosthesis, whether it is attached above or below the knee. The likes of Canadian Rob Snoek, who runs for Canada in the 200m, have perfected their technique to such an extent that he's only a few seconds slower than the world's top able-bodied sprinters.