Is CrossFit Safe for Kids?

The brand behind the high-intensity workouts popular with adults also makes a version for kids as young as three. But is it safe?

Courtesy CrossFit KOP

When I first heard about CrossFit Kids, I’ll admit I was a bit skeptical. Here’s what I know about CrossFit: it’s sweaty, intense and competitive. Is this kind of workout appropriate for kids as young as three—not to mention, safe?

“CrossFit depends on the age of the athlete and their level—that’s true of adults and kids,” says Aimee Lyons, owner of CrossFit King of Prussia who has run the gym’s CrossFit Kids program since 2009. “If I’m working with a kid and I feel like he should be in a different class, I’ll let the parents know.”

Unlike the adult version, fun—not intensity—is the focus of CrossFit kids, the idea being that if you can get a kid to have fun while he or she works out the health benefits will follow. The actual workouts vary by age—at the KOP CrossFit gym, kids are broken into age groups between three to five-year-olds, six to 12, and 13 and up—but they usually start with a warmup, such as an obstacle course, followed by time to work on a skill. Just like with adult CrossFit, form and execution are king here, so kids will work on things like perfecting their squats or push-ups. Then comes the workout, which incorporates what they learned in the skill portion. “So if I taught squats,” explains Lyons, “I might have them do A.M.R.A.P.—as many rounds as possible in X amount of time of five squats, five box jumps and a bear crawl.”

The key is being able to read the kids and gauge how the session is going. Lyons says if the kids don’t seem like they’re having fun, she cuts the workout short and moves on to the next portion: the game. This is the part where the kids really get to be kids. For the little kids, the game might be dodge ball, duck-duck-goose, red light green light or musical medicine balls. For the teens, the game will usually have a skill-focus.

Lyons says some kids average about two to three CrossFit Kids sessions a week. Some are kids of CrossFit parents, of course, but she says she gets a lot of walk-ins, too: kids who say they’re not super in to team sports but want to be active. Some of the older kids use the CrossFit workouts as cross-training for their main sport, like soccer, basketball or football.

It all sounds well and good, but still—what about the safety? It could be too soon to tell either way. “Because it’s still a relatively new phenomenon, we’re just now starting to see injury patterns that are emerging with adults, like certain overuse injuries,” says Robert Franks, sports medicine specialist at Rothman Institute. “So it stands to reason that as these programs become more popular we could start to see the same type of pattern in kids.”

CrossFit, both the adult and kid versions, hasn’t been extensively studied in research or clinical settings. So as of now, it’s mainly anecdotal evidence, some of it pointing to the program’s dramatic successes and some to injury risk. It’s worth noting, though, that in 2008 the American Academy of Pediatrics revised its position on strength-training programs for kids—changing it from a resounding no, to a qualified yes, saying that when done properly, strength-training can have health benefits for kids and won’t negatively impact growth, which had previously been a concern. Some doctors say in older kids, strength training can actually help protect from injury.

Still, it has to be done right: “You want a good mix of activity” in order to safeguard against overuse injuries, says Franks. And you need a trainer who knows what he or she’s doing when it comes to kids and exercise.

Of course, a good dose of fun helps, too.