A dislocated jaw, broken ribs and 20 cases of cauliflower ear hasn't stopped Caroline Portugal from cage fighting.
"Take little diabetes syringes to remove the blood from the broken capillaries," Portugal said. "It definitely kicks your butt. It is the ultimate cardiovascular workout."
Then there's Krizia Carr, who prefers aerial exercises.
"Strength equals confidence. If you don't have that power, you doubt yourself. You think, 'Oh my gosh. I don't want to let go,'" Carr said. "Whatever, you don't want to have that in the back of your mind because then you could make a fatal mistake."
Carr started flying on the trapeze when she was five-years-old.
"It's kind of like riding a bike," Carr said. "Once you learn the tricks, you are pretty much good for a while."
Jodi Hebert also runs through mud and scales walls to get her kicks.
"You get up it, it's like, 'Wow. I did that,' and it's a 10-foot wall, and you're thinking, 'When have I ever tried to climb a 10-foot wall ever in my life?'"
Exercise physiologist Jeanmarie Scordino said people who don't train properly for extreme workouts can end up with knee, lower back, and shoulder problems.
"Some of the stuff that's done is so extreme, and the body is not yet prepared for it. You're inherently going to up the chance of injuries and there are also a lot of heart attacks that occur with a lot of these races," Scordino said.
A study in the Mayo Clinic Proceedings found benefits drop off the longer and harder you exercise, and extreme workouts can damage your heart.
Another study found runners were 19 percent less likely to die than non-runners, but the benefits of exercise decreased for those who logged more than 20 miles a week. The bottom line is if you're going to go extreme, be safe and remember that extreme isn't for everyone.
Also participation in sports, like baseball and basketball, are down 28 percent and 17 percent, but partaking in extreme sports like skateboarding is up 49 percent and snowboarding is up 51 percent.