When Jeff and Mikki Lee Martin discovered CrossFit in the summer of 2003, they couldn’t get any adults interested. Kids, however, were another story.

“Our kids program really started almost a year ahead of the adult program,” Jeff says.

Known as the creators of CrossFit Kids, the couple says trainers must decide that they want to work with children, and then their box has to be “a certain way.”

“We’re devoid of skulls and blood around here,” Jeff says of CrossFit Brand X. “Our box is geared toward families.”

In terms of preparation, Mikki notes, there is a great difference between training adults and training kids.

“The energy that’s required to keep kids engaged is tenfold what it is for an adult class,” she says.

Nonetheless, the athletes are still CrossFitters.

“The kids will make their own community in the same way that adults do,” she says. “They right away relate to other people enjoying the same thing that they’re enjoying exactly like the adults.”