Parkour, the rebel sport that became popular in the U.S. through YouTube in the early aughts, has gone mainstream. The New York Times reports that parkour gyms have been popping up across the country, from Los Angeles to the place where all trends go to die, Williamsburg, Brooklyn. Parkour purists will tell you that the whole point of the practice is to be outside and use your surroundings to create your own obstacle course, even if to the detriment to your own health (and, possibly, life). Bringing parkour inside to a padded gym makes it safer, but ultimately pretty lame.

Parkour enthusiasts say the sport is creative but not competitive. Practitioners use public spaces to perform epic leaps, jumps, and flips, usually while someone films it to throw it up online. While the instances are rare, people have died leaping from one tall building to another. Parkour gyms mediate that risk, but as parkour enthusiast Dan Edwardes told The Times, “if you limit parkour to the indoor setting, you effectively nullify its very point."

Parkour gyms like Bklyn Beast in East Williamsburg feature "juice bars, private classes and children’s birthday parties that cost $450." Parkour could even become the next trendy exercise regimen: "Elizabeth Bellis Wolfe, a 29-year-old lawyer, said she found parkour to be a far more exciting workout than another session on the treadmill." That's probably true, but it doesn't do much for parkour's hardcore reputation. 

Eventually, everything cool gets co-opted by 29-year-old lawyers looking to break a sweat after a long day writing briefs. For those mourning the loss of true "street" parkour, you can always watch old YouTube videos. 

Photo of a youth practicing parkour in China, via Stringer for Reuters.