With its "really unique" emphasis on boxing, a new Ashland gym does much more than help Erin O'Kelley Muck to roll with the punches.

With its "really unique" emphasis on boxing, a new Ashland gym does much more than help Erin O'Kelley Muck to roll with the punches.

At Aerospace High Performance Center, Muck no longer wonders whether she is exercising her core — or which muscles constitute that buzzword body part.

"I know where it is — I can totally tell," says Muck, 40. "It's probably the best core workout I've ever had."

Twisting torsos while throwing punches characterize the regimen developed by former professional boxer Michael Olajide in New York City and transplanted to Ashland in October. Aerospace group classes also incorporate jumping rope, light weight lifting, calisthenics, plyometrics and even dance maneuvers. Without cardiovascular or weight machines, Aerospace provides intense cardiovascular exercise that simultaneously builds and sculpts muscles and hones coordination and concentration, says Michelle Ronsen, owner of Aerospace Ashland.

"It's really one of the only forms of upper-body cardio," says Ronsen. "It defines your body in a different way."

A self-described "workout fanatic," Ronsen, 42, ran across some videotapes produced by Olajide and former professional ballet dancer Leila Fazel. The Ashland resident decided to check out the gym on a business trip to New York with her husband. Intending to give other gyms a shot, Ronsen says she never looked any farther than Aerospace, the first activity to truly engage her since she played college volleyball.

"I wanted to bring that passion to where I live."

That passion is palpable among gym members and visitors in the first month of Aerospace Ashland's operation.

"Awesome! Thank you so much," exclaims Muck after a short session of punching trainer Sarah Holgen's mitts. Muck's one-on-one work follows more than hour of Aeroimpact, the group class that most replicates a professional boxer's training.

Participants sport boxing gloves even as they stretch and perform a series of warmups — squats, lunges and pushups balanced on the gloves' puffy knuckles. Demonstrating the knees-bent crouch used in the boxing ring, trainer Brandon Baldwin sets the pace for shadowboxing: slow, controlled jabs that soon double-time for dozens of sharp punches. After landing hook shots on thin air, students move to the gym's Impact Room to hit something solid.

"It kind of sounds masculine," says Ronsen. "But the beauty of this is that it's so cross-gender.

"Hitting something feels so good."

Pummeling the gym's speed, heavy, double-end and body-snatcher bags for nearly an hour, students are prompted to maintain proper stance and rhythm. Punching hard isn't the point, but rather tapping into the endurance needed to connect with the bags over and over and over.

"That's something new for me," says 37-year-old David Simms of the Aeroimpact class. "Within 15 minutes, my shirt is soaked."

Teeth grit as Baldwin claps out a faster tempo for the group's hooks, followed by uppercuts. The more seasoned students stay light on their feet, bouncing to the rhythm of each punch and retracting their fists to shoulder-height. Set to blaring music, the workout progresses to more complicated, one-two punches with fists alternating and shoulders dipping to dodge imaginary blows.

"A hundred percent of the time ... it engages your mind," says Ronsen. "At the same time, you are gaining a skill: I could really get in a fight and protect myself."

Less "glamorous," says Ronsen, than boxing's choreography is the sport's classic mode of conditioning: jumping rope. A component of most Aerospace classes, jumping rope for 30 minutes nearly nonstop is the format for the beginner and intermediate Aerojump sessions, each offered twice per week. Anyone inclined to write off jumping rope as the stuff of grade-school playgrounds, says Ronsen, need only attempt some of the class's "tricks" — crossovers, double turns, squatting, one-legged and slow-motion jumps.

"It's humbling," says Simms, who characterizes his athletic abilities as above-average. "You realize there's muscles in your legs you never thought you had."

The "semisquat" position preached and practiced at Aerospace, says Muck, makes for more of a lower-body workout than newcomers would expect. Calf muscles are challenged by repeatedly springing up out of the boxer's stance, adds the Ashland resident, explaining that her legs were more sore than her arms.

"We're going for long, lean, sleek muscles," says Ronsen.

Fast-twitch muscles also get quicker after a few weeks of working out at Aerospace, says Simms. Annual membership with monthly dues grants access to the gym in New York, where Simms travels for business. The Ashland resident says he was impressed by how closely Ronsen's gym — Aerospace's first franchise — adheres to the philosophy of Olajide, who at age 51 can "run circles around a 15-year-old."

"We can reprogram our bodies," says Simms. "We can reprogram our muscles.

"There's whispers of excruciating pain in there, too."