You may not know who Dion Emilia is, but if you’ve explored the trove of training videos on YouTube, you might recognize know him as the star of one of the most gritty, brutal and innovative homemade TRX videos on the site. His most popular video has garnered more than 27,000 views. It features Emilia...

Brandon Vera doesn't lift weights, he uses the TRX to stay strong in the ring. "It'll work muscles you didn't even know you had...everything is core related. Any exercise you do on the TRX is core related. Your body hurts the entire time."

Roger Huerta rocks out on the TRX as he runs through his training routine.

Just when you think it couldn’t get any harder, think again. Week 11 and 12 are the hardest of the program! This is a build up program, with no off time or tapering, advancing each week. This week we jump to three sets of each exercise, reducing and sometimes eliminating completely the rest between sets...