"I'm a rabid libertarian," says Greg Glassman, 56-year old founder of the worldwide fitness phenomenon called CrossFit.

Glassman opened the first CrossFit gym (or "box" in CrossFit lingo) in the mid-1990s in Santa Cruz, California. Today, there are more than 7,000 CrossFit affiliates around the world. These affiliates are not franchises, they're independently operated boxes owned by entrepreneurs who pay $1,000 to get certified as a CrossFit trainer and then pay $500-$3000 annually for the right to use the CrossFit brand. Each affiliate is free to innovate, which makes CrossFit a kind of open-source fitness community. Despite—or because of—its unconventional approach, CrossFit is projected to generate $100 million in revenue this year.

As independent in his exercising as he is in his politics, Glassman's relentless focus on results has created an army of athletes who have left conventional gyms for the allure of the "WOD" (CrossFit's "workout of the day").

Every day a new WOD is posted on the CrossFit website, and all around the world people compete against each other to complete a series of constantly varied, high intensity, functional movements (squats, sprints, pull-ups, dead lifts, and more). WODs aren't easy, and it's not uncommon for "CrossFitters" to vomit after a particularly difficult workout (they call it "meeting Pukie," Crossfit's puking clown mascot).

CrossFitting is not just about difficult competitive workouts, though. It's also about being a member of a supportive community. A Green Beret told Glassman that doing CrossFit helped him realize that the secret to developing the camaraderie necessary for special-forces units is to combine agony with laughter.

CrossFitters are also unconventional when it comes to diet. Instead of the grain-based dietary recommendations of the U.S. Department of Agriculture, CrossFitters tend to eat a paleo-style diet heavy on meat and unprocessed foods. "Our view," says Glassman, "is that grains are best consumed by livestock, and what homo sapiens need is a diet of meat and vegetables, nuts and seeds, some fruit, little starch and no sugar."

CrossFit is not without its critics. Many conventionally minded trainers believe that the intensity of CrossFit workouts increases the chances of injury. Others, noting the paleo diet, the functional movements and the extraordinary enthusiasm common among CrossFitters, liken CrossFit to a kind of caveman cult. Glassman's response? "The caveman thing? Yeah, I'll tell you what. I don't think it's an insult to any CrossFitter."

The 2013 CrossFit Games start today and culminate on Sunday, July 28, when the winners will be crowned. This year, around 140,000 athletes from around the globe entered the open competition. CrossFit fans can watch live streams of the event Monday-Thursday on the CrossFit games site. The games will be covered by ESPN3 and ESPN2 on Friday, Saturday and Sunday.

About 9 minutes.

Produced by Paul Feine and Alex Manning.

Scroll down for downloadable versions and subscribe to ReasonTV's YouTube Channel to receive notification when new material goes live.