Passersby that peer inside the windows of CKO Kickboxing won’t see treadmills, ellipticals, or stairclimbers. Instead, they’ll spot rows of heavy bags lurching backward and sideways from the force of participants’ kicks and right hooks. The kickboxing-focused gym doesn’t need excessive equipment or a catalog full of workout programs—the high-intensity fitness regimen of kickboxing is more than enough to shape up CKO members. Students of all ages reap the system’s multifaceted benefits, burning up to 1,200 calories per class, releasing stress, and developing a six-pack more realistically than drawing on their midsections with a marker. There is no beginners or advanced classes, anyone can do it at their own pace.