Southern California is no stranger to the workout trend called CrossFit. The gyms, or "boxes" as they're known, have been popping up in cities across the country since the workout caught on in the early 2000s.

The exercise trend focuses on explosive movements called 'plyometrics' and high intensity, high volume workouts meant to confuse and strengthen the muscles. CrossFit has become a national phenomenon with more than 5,000 affiliated gyms across the U.S.

But a recent serious injury at a CrossFit-style competition here in Southern California is bringing more attention to the safety of the program. The athlete, experienced CrossFit trainer Kevin Ogar, is now paralyzed from the waist down after being injured while doing a routine power lift at the competition.

Beyond the headline-grabbing serious injuries, does the nature of the CrossFit-style workout make people more prone to injury? Is CrossFit inherently dangerous or do the benefits of exercise outweigh any risks? Is CrossFit riskier than other types of sports? Will CrossFit athletes of today be casualties in a decades’ time? With its increasing popularity, can CrossFit gyms and trainers safely keep up with the growth?

Guests:

Andy Galpin, PhD, assistant professor of kinesiology at Cal State Fullerton

Jonathan Sum, assistant professor of Clinical Physical Therapy at USC