MINNETONKA, Minn. (WCCO) – Ever have one of those days you just want to punch a pillow? There’s a new gym letting you do that, and you can even step into the boxing ring.

GymJab in Minnetonka lets you get out some aggression while burning fat and calories.

Owner Allan Charney says, when he launched GymJab in search of a new way to work out, he “wanted a gym that would transform people’s bodies and lives.”

They do that with interval training, moving the heart rate up and down. Natalie Kane took Cardio Jab, which spiked and lowered heart rates through rounds of exercises.

Here’s how GymJab is different. Everyone in the class has to wear a heart rate monitor, which connects to your body, reads your rate and broadcasts it up onto screens that are throughout the gym. So you can tell who’s working hard and who’s hardly working.

“For me it’s really motivating,” said gym member Allan Charney. “There’s no lying. You have to have the numbers to prove it.”

Call it accountability. The intervals are based on your heart rate and what it takes for you to reach maximum capacity, not your neighbor.

The monitor shows you which of five zones you’re in, from gray (zone 1) all the way up to red (zone 5), where you’re burning at your maximum heart rate.

That sort of interval training helps you burn fat and calories more efficiently during the class and keep burning after the class.

If you’re think you’re not into boxing, you may be surprised to find it’s actually pretty basic.

“What we’re doing here is not trying to groom professional fighters. This is all about the average Joe and JoAnn,” said Charney.

The circuits are accessible, and it doesn’t matter your fitness level.

GymJab is located in Minnetonka. Single sessions start at $19. If you buy an unlimited membership, it’s $89 monthly.