Ledyard — In some fitness classes, the instructor remains immobile, barking out orders and only occasionally demonstrating a move or position. A participant glares at her teacher, thinking how rich it is that he just sits there while droplets of sweat coalesce between her aching shoulders.

Chris Pennenga is not that kind of instructor.

When his students kick their punching bags, he kicks. When his students throw medicine balls to the ground, he throws one, too. When his students go into plank position, he's right there with them.

He does this while shouting, "C'mon, c'mon, c'mon, c'mon!" and saying playfully, "You pay me to torture you!"

Pennenga, who holds a fourth-degree black belt, opened Main Event Boxing at 1663 Connecticut 12 on Tuesday. The studio offers boxing classes Monday through Saturday for participants over age 13, and taekwondo classes three days a week for kids ages 5-16.

Taekwondo is $119 per month while boxing is $99. Pennenga is running a $75 per month special on boxing classes until Nov. 1, which includes wraps and boxing gloves.

Pennenga, 55, ran New England Martial Arts Academy from 2001 to 2012, taking a five-year break for personal reasons before opening Main Event Boxing.

From 1980 to 2001, he served in the Coast Guard, living in New York, California, Alaska, Texas, North Carolina and then Connecticut. Pennenga has been living in Gales Ferry since 1998.

His military background shaped his teaching by giving him a focus on discipline and teaching. He said his attitude toward boxing students is, "No excuses, no complaining, just do it, work hard and you'll get good results."

For martial arts, he makes the kids earn their belts. Pennenga is not about to give out a belt just so a student can progress, and he estimates that he's only promoted 100 black belts in 17 years of teaching in packed studios.

While he noted that the area around Main Event Boxing is saturated with martial arts studios and gyms, he is confident he has a good program and his business will be a success.

Pennenga, who also works part-time in security, is teaching all the classes, but he will soon bring in some of his former instructors. He also plans to add 15 punching bags to the existing eight.

At the 9:30 a.m. boxing class on Thursday, Pennenga had two students, Monique Spotts and Amy Kersteter. Spotts has been doing kickboxing and taking classes with Pennenga for years, but this was only Kersteter's second class.

It was a whirlwind 50 minutes of three-minute rounds at the punching bag intertwined between push-ups, skater hops, bicycle crunches and other exercises, with an aural backdrop of pump-up pop remixes.

"I have a gym membership that I don't use because it's boring," Kersteter said at the end of the class. "I'm canceling my membership to do this."

She came with Spotts, a former co-worker who got into kickboxing after her kids started taking karate.

"It works your whole body without you knowing it," Spotts said. Compared to going to the gym, "there's no such (thing as) leg day or arm day at a kickboxing studio. It's body day."