When your dad is Ozzy Osbourne, it might be hard to keep the crazy train from going off the rails. Jack Osbourne says he went from a sedentary childhood to being "a pothead party animal," then got sober. But he also grew bored.
"I started looking at options for what was fun," Jack said, now 31. "I got into rock climbing and through a desire to get better realized I needed to be fit."
That's what led to the launch of his reality show "Jack Osbourne: Adrenaline Junkie" in 2005. He trained in Muay Thai in Thailand, ran with the bulls in Pamplona, climbed the face of El Capitan in Yosemite — all in the first season.
In 2012, he was diagnosed with multiple sclerosis, but that hasn't slowed him down.
The autoimmune disorder affects 400,000 Americans, and the course it takes is rarely predictable. Eighteen months after his diagnosis Jack had the opportunity to be on "Dancing With the Stars" — a physically grueling endeavor — and said the idea was daunting.
"It was a challenge I wanted to pursue because everyone thought I couldn't," he said. "I want to dispel myths about living with MS."
Jack figured he would be voted out after a few weeks. "Thirteen weeks later I was wondering what I'd signed up for." He and his partner finished third.
Osbourne said his MS did start to rear its head in different ways during the dance show. "I started having issues with balance, and there were bouts of fatigue."
The treatment was no late nights. "I would dance, then go home and go to bed."
Jack has continued to stay active despite his diagnosis. "There's no science showing exercise helps battle MS, but my philosophy is a body in motion stays in motion. I'm stronger than I've ever been."
He does CrossFit three times a week, continues rock climbing and loves to surf. He also enjoys adventure races and obstacle courses such as the Spartan Race. He's currently training for the American Sniper Challenge, a 48-hour footrace that also involves target shooting.
Another passion is his website, created with help from experts at Teva Neuroscience as a resource for others with MS.
"The motivation behind YouDontKnowJackAboutMS.com is that I spent a lot of time researching my condition, looking for a one-stop website to get all the information I would need, but not in a clinical way," he said.
And when he didn't find it, he created one.
"My approach with the site is about having a positive outlook. Not everyone can do CrossFit three times a week, but maybe they can get out and walk their dog. It's different for everyone."
He's not prescribing exercise as a cure-all but hopes to "make the message as diverse and inspirational as possible."
"I'm stuck with it," Jack said of his MS. "It isn't going anywhere. My outlook is the thing I can change."
Fell is a certified strength and conditioning specialist and owner of bodyforwife.com.