Freerunning is the sport of running through streets and public places, jumping between walls and buildings, vaulting obstacles, and treating the city as a kind of open gym. A person who does it is a freerunner. Though actually, it sits next to parkour rather than being a perfect copy. Parkour (from French) is often taught as efficient movement from one point to another. Freerunning, from free + running, more often includes acrobatic, playful, or showy moves. English speakers, and almost all Taiwanese students, still lump both under 跑酷 unless they are deep in the sport. It is informal, physical, and urban. You will see it in videos more than in office English. “Free” is about the open environment and the style of movement, not a free ticket.

跑酷、自由跑（在城市裡跑跳翻越）。台灣口語幾乎都說跑酷。