Jousters like Andrews use bigger horses than their medieval counterparts because they themselves are so much bigger than the knights of old. Their mounts are 2,000-pound draft horses — Percherons, Clydesdales and Belgians. If you add the weight of horse, rider, saddle and armor, you end up with something like 2,500 pounds at either end of the list moving toward each other at about 25 miles per hour. Roy Cox, a pioneer of American jousting, calculates the force of the resulting impact as 50,000 pounds per square inch. ‘If you want to experience that for yourself,” he says, “put your thumb down on the cement, take a sledgehammer and slam it really hard.’

NYT, “Is Jousting The Next Extreme Sport?”