If there was ever a way to score some amazing biceps and chiseled abs, New York's popular Rumble Boxing is it.

Fitness junkies may have heard the buzz around the city the last several months...Rumble is coming. And for good reason: While San Francisco has a wide array of workouts, we haven't seen the intensity and energy of a Barry's Bootcamp class combined with boxing—until now. With a new Sansome Street location, Rumble is coming in hot.

So WTF is Rumble, anyway? It's an intense and sexy—yes, sexy—45-minute, 10-round athletic workout that alternates between punching heavy bags to carefully choreographed sequences, as well as floor work where you'll find yourself lunging, squatting, and maybe even doing some Russian twists and nasty planks. It all goes down in a dark room with loud hip-hop beats, and classes are taught by some of SF's finest instructors.

The 45 minutes will pass before you even have time to blink and, when you're finished, you'll feel like you deserve a badge of honor for surviving. I walked out of a Rumble class last Friday—led by legendary local trainer Alvin Holden—drenched in sweat, with arms like jelly from all the punching, my legs wobbly from all the ducking and squatting—and I loved it.

The best part about Rumble is that you don't need to have prior boxing experience. The instructors walk you through each round so you know what to expect at all times. And for all you seasoned boxers, don't walk in here thinking it's going to be an easy workout. You, too, will get your butt kicked.

// Rumble classes are $34 for 45 minutes; 180 Sansome St. (FiDi), rumble-boxing.com.