(WUSA) -- Have you seen all those infomercials touting one fitness system or another? Or, maybe your girlfriend SWEARS by a cross-training group she just joined. All good ways to help you get in shape. But some workout crazes can be dangerous to people without the right level of fitness.
Sonja Nesbit of Washington, D.C. is one such example. She received a 'daily deal' email offering an early-morning fitness boot camp at a low price.
Sonja started the boot camp last April, and during the fourth session, suffered a painful meniscus tear in her knee.
Sonja describes what happened. "I was doing an exercise where you lunge forward and grab things. It works on your quads and your calves and it did not go right for me. I knew right away when I felt a burning in my knee."
"I had to have arthroscopic knee surgery to repair the meniscus tear. I can't even begin to think about how much money I spent fixing my knee as opposed to perhaps getting involved in that boot camp deal that I found. One of the web specials that come to your computer every single day; not such a good deal at the end of the day," she says.
Not to mention being sidelined by an injury that left Sonja unable to work out at all, and gaining back the weight she wanted to lose.
Arlington, Virginia orthopedic surgeon Dr. Derek Ochiai says he is seeing more cases of overuse injures, as well as knee, hip and back problems among novices who try to embrace the latest workout trends, including P-90X, Cross-Fit and Insanity.
Dr. Ochia says, "A lot of these programs are very intense and they're actually meant for people who are already in shape. It is not necessarily for somebody who is leading a very sedentary life to jump into."
Dr. Ochiai says less physically-fit people can certainly try the workouts, but start at a beginner level.
He cautions people working out at home, "Just because it's on a TV screen doesn't mean you have to do what the person on the screen is saying right then. You can ease into it, you don't have to do all the reps that you're seeing the person on TV do, you can do less.
"(Another) danger is people who do an exercise for a little bit of time, lose interest, do it again, then lose interest. That stop-start can really set you up for injury. When you start-up again, you are thinking you're at the same level as when you stopped doing it, which could've been 4, 6, 8, 12 weeks prior. And you've actually lost some ground. If you go right back to the level of workout you were at before, then you can get injured."
But even conditioned athletes can get hurt when they try a new trend. Michael Hmara of Sprigfield, Virginia, is an avid runner who decided to switch from traditional running shoes to Vibram FiveFingers, minimalist footwear that emulates running barefoot. The idea is to change the way the foot strikes from the heel to the mid and fore-foot, eliminating jarring and joint pain. But it was just the opposite for Michael, even though he broke in the five-toed shoes over time.
Hmara says, "I gave it about four months, just walking in them everywhere, taking my time, not forcing the issue. The more I started to run, the more my back started to hurt, and it was like I got to the point where I was just like 'I'm done.' I want to run , but I don't want the pain. So I stopped and went back to a normal shoe and it was perfectly fine."
On its website, the maker of Vibram FiveFingers shoes says some initial discomfort isn't unusual, depending on foot type and running style. But if the pain persists, they say stop using the shoe.
So, how do you embrace a new workout trend safely?
Sports medicine experts offer this advice:
Build up your cardiovascular fitness first. Taking power walks may not seem as exciting as P90 X, but they will get your heart pumping.
As Dr. Ochiai mentioned, work up to repetitions and intensity. Squats, lunges, upper body and core work are all great, but an unconditioned body risks injury. Don't immediately try to match the level of the instructor in the video, or the person running your boot camp.
Consider investing in one session with a personal trainer, who can take you through the gym and set up an individualized workout that fits your fitness level.