"... Fitness culture couldn’t have changed more significantly since the late ’60s. Back then, residents of my small Southern hometown would spot my father, an early jogger, and yell out of their car windows, “Keep running, hippie!” These days there aren’t that many joggers in my Los Angeles neighborhood, but every other block there’s another fitness center offering boot-camp classes or Brazilian jiujitsu, with people inside punching, kicking and yelling at one another like drill sergeants. ..."
Read the entire article: http://www.nytimes.com/2014/10/19/magazine/why-are-americans-so-fascinated-with-extreme-fitness.html