Ninja Gym For Kids Mixes 'Floor Is Lava' Vibe With Skills In Howell

HOWELL, NJ — Finding ways to get children active while keeping it fun is a challenge many parents face.

Jeff and Gina Miranda have opened a new gym in Howell they hope meets those needs while also helping to build up the confidence of their kids.

It's not simply a scaled-down version of an adult gym with adult-style fitness routines, however. USA Ninja Challenge is the fun of the "floor is lava" activity with a kid-sized flavor of "American Ninja Warrior".

There are obstacles and rope climbing and monkey bars to test out, and pads laid out to follow a path around the gym.

"It's similar to a lot of things we did in the military," Jeff Miranda said.

He learned about USA Ninja Challenge when he was searching for veteran-friendly franchises to change course and start a new business. He had enlisted in the U.S. Army right out of high school and served in Iraq in 2004 and 2006. When he left the service and tried to return to civilian life, the change was difficult and Miranda said he struggled for a few years with the challenges of fitting back in.

A brush with celebrity led to connections that put him on CMT (Country Music Television) with a pair of shows, "Sweet Home Alabama," where 10 city guys and 10 country guys vied for the affections of a Southern belle, and "Southern Nights," which Miranda described as a cross of MTV's "Real World" and "Jersey Shore."

Miranda also got into the duct cleaning business, first working for a guy he met at the gym then opening his own duct-cleaning business in 2012. After Gina, who is a physician assistant at an urgent care in Manalapan, gave birth to their son, Jeff found he wanted to make a change.

"I really wanted to get out of the in-home service business and spend more time with my family," Miranda said, "something that allowed me to give back to the community and make a living."

That's when he found USA Ninja Challenge. The Mirandas took the leap in 2024, buying two USA Ninja Challenge franchises. The Howell site is holding its grand opening celebration on June 17, and Miranda said they are working on plans to open the second site, possibly in Ocean County.

"It’s just something I fell in love with," Miranda said of USA Ninja Challenge. It reminded him of the training he faced when he enlisted in the Army, which challenged him to get stronger, more agile and built his fitness.

The program is essentially a workout disguised as play. While kids think they are just trying to "avoid the lava" by staying off the floor, they are actually progressing through a structured, six-level curriculum that combines gymnastics, climbing and cross-training.

The levels are not linear — a child can achieve a level in each of the various skills and apparatus independently, which helps children build confidence, Miranda said.

At first glance, it can appear there is no structure to the play, he said, but parents have told him they see the difference the program is making with their children.

"I've seen them grow so much in confidence," as they take on challenges such as wall-climbing or the ropes. The hour-long classes also have the children building friendships, he said.

He has seen it with his own son, who's 3.

"He wants to go every day," Miranda said. "His confidence is skyrocketing — now he’s doing all this stuff I didn’t expect him to do."

Miranda said there's one drawback.

"He’s really good at what he does but he doesn’t listen" and follow along with the instructions, Miranda said with a chuckle.

In addition to the classes, USA Ninja Challenge offers its own circuit of competitions, Miranda said, similar to American Ninja Warrior. The gym includes a kid-sized wall similar to the one at the end of the American Ninja Warrior courses. The USA Ninja Challenge includes a national championship in Katy, Texas.

The organization also has partnered with USA Pentathlon Multisport, as ninja warrior-style obstacle course competition is replacing equestrian show jumping in the modern pentathlon at the 2028 Olympics.

Miranda hopes to have a competition team next year, he said.

Miranda said the Howell location offers programs for children from ages 4 to 17, and will soon be offering a program for 2-1/2- to 3-year-olds called Sidekicks, where they will be allowed to be accompanied by a parent or guardian on the course.

"That's the only time parents are allowed in the gym," Miranda said.

Parents can sign their children up for a free trial course, and Miranda said the gym does not require lengthy contracts; memberships are month-to-month.

"Pick a time and day that works. There's no strings," he said. "We just want people to come in and try it out."

There also are weeklong summer camps where the children attend three hours a day and participate in activities including obstacle racing, wall climbing and other summer camp games.

Membership is not required to sign children up for summer camp.

Miranda also aims to do fundraisers with the community, something that is part of USA Ninja Challenge's mission.

"I hope I can make a difference in these kids' lives," Miranda said.