Zip Line time

One of the fun parts of living at Red Moon Road for the past year and a half has been the beloved zip line! Sunday afternoon, Lindsay's sister Jen enjoyed a ride.

CrossFit: The Fast, Furious Workout Craze
Can CrossFit whip you into shape in just 15 minutes a session—safely?

If your gym suddenly looks like a cross between a gymnastics studio and a Marine Corps boot camp, chances are it's offering CrossFit classes. This fitness craze that's swept the nation in recent years was developed by a former gymnast in Santa Cruz, California, named Greg Glassman. The grassroots movement started with Glassman's rudimentary Web site on which he posted a daily workout routine (officially known as the "workout of the day" or simply the "WOD"). A dedicated following of police officers, firefighters and military types soon discovered the workouts, and from there, the wave just kept growing. Now, CrossFitters (as devotees are called) number in the thousands, and gyms across the country are offering this intense workout program.

"The workouts include elements of Olympic weightlifting, gymnastics, and track and field done in combinations that increase core strength and conditioning," explains Jake Platt, owner of Northwest CrossFit in Seattle. There are about 50 basic exercises that are mixed and matched to create the "WOD," and every day is different. "Routine is the enemy," says Platt, an N.A.S.M. Certified Personal Trainer. "We want to keep your body guessing and make sure that no adaption is happening that will lead you to plateau and stop seeing progress."

That variety is one of the biggest selling points of the program. "I had been going to the gym for about six months, and I was just bored with it," says Roger Parks, a software engineer in Seattle who discovered CrossFit four months ago. He has now traded his hour of treadmill time for a high-intensity CrossFit session four to five days a week. "Now I crank through my workout in 20 minutes and then I'm done for the day," says Parks. He also supplements his workouts with biking and running, and has seen his flag football and soccer playing improve thanks to the strength and stamina he's gained doing CrossFit.

Efficiency, intensity—and safety concerns

CrossFit workouts are modeled on full-body functional movements—like lifting, pulling, twisting, running, crawling and pushing. And because every move is designed to incorporate the entire body, a full workout can be accomplished in an efficient 15- to 20-minute session. The other trademark of the sessions is their intensity. "We're looking to get people to move as quickly as they possibly can through the entire workout," says Platt.

Critics of the workouts (and even some CrossFitters themselves) worry about the high intensity of the moves. "You're doing things fast with a bunch a weight, and I can see how that could be dangerous if it's done wrong," admits Parks. To avoid any potential risk, Parks started slowly. At the CrossFit gym he attends, the "WOD" comes in two versions—the prescribed routine and a modified version of it. Trainer Jake Platt agrees that there could be potential for injury if the moves aren't done perfectly. "Safety is our number-one concern, so in the beginning we work on very basic exercises and make sure people are learning perfect form and movement," he says. That's especially important considering the weights that are used in the exercises (for example, a 20-pound "wall ball" for men and a 12-pound one for women, or a 75-pound Olympic bar for men and 50-pound one for women).

Don't jump in too quickly

But not all CrossFitters or instructors are such sticklers about technique. "There's a very macho, 'be all you can be' attitude that surrounds this program," says Ralph LaForge, M.S., a physiologist at Duke University. He's bothered by the risk of musculoskeletal injuries—especially when older or relatively unfit people jump too quickly into the fast-paced, hardcore workout. Participants often brag about their soreness after a session, but LaForge worries that the competitive atmosphere can push people beyond their abilities. "When you have really debilitating soreness, you've actually ruptured muscle fibers," he explains. "And if you go back and do it again before you've fully recovered, you are more prone to injury."

That "no pain, no gain" mentality has been a cornerstone of CrossFit, but there's also a push to make it more palatable to the masses. Stories abound of CrossFitters boasting about workouts that made them throw up (some even sport T-shirts declaring "I met Pukey"), and others have ended up in the emergency room with life-threatening cases of rhabdomyolysis, a condition caused when muscle fibers break down, release into the bloodstream and may poison the kidneys.

"There are a lot of unqualified coaches teaching this, and anyone can go on the Web site, get the workout, and push themselves too hard," says Platt. "I'm trying to change that concept and show that CrossFit can be a program that everyone can benefit from, and that they don't have to be pushed to the brink of throwing up in order to see results."

Measuring the results

Potential pitfalls aside, CrossFit is generating results for its thousands of followers. "I like the measurability of it," says Parks, who felt like he had plateaued at his regular gym routine before turning to CrossFit. Not only has he replaced an extra 30 pounds with a new set of totally toned, 6-pack abs, but he can look back at his records to see exactly how much faster he can perform certain sequences, how much more weight he can hoist, and how many more pull ups he can do now compared to when he first started CrossFit. "Being able to measure results is a big deal for me, and for the other people I work out with at the gym," he says.

To find a CrossFit trainer who will push you to achieve results—but do so safely—Platt recommends visiting a club to watch a class, perhaps participate in a free session, and to speak with the trainer about his or her CrossFit and overall fitness philosophies. Ideally, you want to see a mix of people participating in the sessions—young, old, male, female, athletes and fitness newcomers. And you want a trainer who understands the different ability levels of these different populations and tailors the prescribed workouts to suit individual needs.

First Person: A CrossFit Skeptic Becomes a Convert

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Sally Wadyka is a Boulder, Colo.–based freelance writer who writes regularly for Shape, Runner's World, Real Simple and The New York Times.