Kids increasingly are working out at boutique gyms, where they’re taking classes in strength training, spin and yoga. Is that a good idea?

That might seem like a strange question to ask at a time when childhood obesity is making headlines. In theory, anything that gets kids moving is good, said David Berkoff, a sports medicine doctor and professor of orthopedics at the University of North Carolina at Chapel Hill, because “we have such a crisis of overweight and under-exercised kids.”

But experts have some caveats when it comes to youngsters taking fitness classes designed for grown-ups.

“Kids are not miniature adults, and I would caution against kids taking classes that are formatted the same way as the adult classes,” because they may not be age-appropriate, said Rick Howard, assistant professor of kinesiology at West Chester University and co-author of the National Strength and Conditioning Association’s 2016 position statement on youth training.

Parents should look for studios that cater specifically to children with separate class times, equipment and instructors and employ safety measures such as separating children by age group, he said. Here’s how gyms are accommodating their new young visitors.

Strength training

It may surprise parents to learn that strength training can be highly beneficial for children. Body-weight exercises and light to moderate weightlifting can help build stronger bones, increase bone mass, reduce the risk of injury and help kids move better, said Berkoff, whose 11-year-old son regularly attends CrossFit classes.

“The key is for strength training to be structured and supervised,” he said. “I wouldn’t let my 11-year-old head to the CrossFit gym alone to do clean-and-jerks with the adults there.”

Teens should not aim to build muscle bulk, said Shari Barkin, chief of general pediatrics at the Monroe Carrel Jr. Children’s Hospital at Vanderbilt University. “Until you reach your skeletal and physical maturity, you do not want to be building muscle. We recommend using light weights with high repetitions. The goal is to focus on fitness, strength and safe technique.”

Spinning

Children’s spin classes are less common because most spin bikes can accommodate only riders 4-foot-10 and taller, but many studios allow teens to attend adult classes with parental consent.

At Saratoga Cycling Studio in Saratoga Springs, N.Y., owner and instructor Angela Amedio has created a teen program that welcomes pre-scheduled groups, such as sports teams from the local high school. She tailors the class routine to each group’s needs — some hope to increase endurance, others to build community and confidence. For teens who are less athletic, “it’s a nice way to get active with your peers, because there’s no pressure, no competition,” she said.

Yoga

Barkin recommends kids’ yoga classes, for physical and psychological benefits, such as improvements in strength, flexibility, balance and relaxation. In Los Angeles, Zooga Yoga offers classes for kids of various ages, including parent-and-me classes where children and adults exercise together. Rather than hiring traditional yoga teachers, however, studio owner Antonia King recruits preschool teachers and trains them specifically for kids’ yoga.

“What I don’t recommend for kids, or for teens, is hot yoga,” Barkin said. “Hot yoga tricks your body into thinking that you can do more stretching. For kids especially, it’s important not to overstrain their muscles.”