Overview: Rugby meets mixed martial arts in the brutally violent calcio storico, a traditional sport of Florence, Italy, that dates back nearly 500 years.
Overview: Scotland's Highland games combine a cultural celebration with challenging athletic tests of strength — including the unique caber toss.
Overview: For many in the Philippines, freediving without oxygen is a way of life. It's also a demanding sport that pushes the limits of the human body.
Overview: In Austin, Texas, skaters find an inclusive and supportive community in roller derby, a competition that blends high speed and physical combat.
Overview: In Kyrgyzstan, players throw themselves into the national sport of kok boru, a rough pololike game played on horses — with a dead goat as the ball.
Overview: Professional wrestling in the Congo mixes athleticism and showmanship, but adds a layer of voodoo mysticism that makes it unlike anything else.
Overview: Unique to Bali's Jembrana region, Makepung Lampit puts its own spin on drag racing. The vehicle is a water buffalo, the track a flooded rice field.
Overview: Athletes have grappled in Pehlwani wrestling contests for centuries in India. Now women are competing in an arena once reserved for men.