We tried it: H.I.I.T. It Hard at Relentless Fitness

The disclaimer is there: This class is not for the faint of heart.

"I really think it's important to have a solid base of strength fitness under your belt," Michele Rogers, resident muscle mechanic at Relentless Fitness, said of her 'H.I.I.T. It Hard' ­ high intensity interval training class.

After running eight miles on Kelly Drive Saturday, and playing hours of full court basketball Sunday, I thought I at least had the stamina to withstand an hour of this high intensity workout. But on a rainy Tuesday night inside the cozy boutique fitness studio in Washington Square, I found myself more drenched than if I had stood outside.

The fun, fast-paced 'H.I.I.T. It Hard' small group class combines elements of cardio, strength training, and speed and agility drills. I needed to towel off after the warm-up.

The tabata-style cardio segment featured just 10 seconds of rest between intense 20-second intervals of moves like mountain climbers that won't let your feet get too acquainted with the ground.

Next came a full-body strength training circuit that includes weights, ab work, jumping, and pushup and pull-up techniques. While there are elements similar to CrossFit, Rogers stresses body awareness and proper form — crucial aspects of fitness and injury prevention that can be lost in CrossFit's absence of mirrors.

"I try to look at everybody for their body and teach them how to become aware of their body," said Rogers. "I want to combine that body awareness, and control and form, with challenge — getting people to push themselves beyond their limits."

Those limits are tested throughout the workout, especially in the speed and agility finale, featuring suicide sprints, ladder drills, and treadmill sprinting to the max.

"What's the fastest you've ever gone on a treadmill?" Rogers will ask. "Oh, 10 miles per hour? Good, you're doing 11. People always look at the numbers, look at the weights, and stop themselves mentally. I try to push people past that safely."

In addition to classes like this one, Relentless Fitness (founded by Roger Dickerman and Melissa Pellegrino) also offers private training, a Biggest Loser-type transformation program, and a kids' gym with promising young gymnasts. The focus here is on the individual, with trainers who work to promote safe, healthy challenges.

If you haven't done much interval or strength training, 'H.I.I.T. it Hard' will have you walking around the next day like a newborn calf or a just-oiled Tin Man, with sore muscles that serve as reminders of a comprehensive work out that was, well, relentless.

Relentless Fitness, 249 South 10th Street, Phila, Pa. 215-351-6260. relentless-fitness.com

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