5 Fun Reasons To Get Back To The Gym

LOS ANGELES

The Class

Rocket Workout

Where Crunch ( crunch.com)

What it is A routine using a soon-to-be-everywhere machine called the Orbital 360. You'll spend 30 minutes sculpting your body with variable resistance poles that are anchored to a circular platform. The Rocket Workout includes strength-training exercises as well as stretches and Pilates moves, all using the poles for support.

BOSTON

The Class Burn

Where Healthworks ( healthworksfitness.com)

What it is A group class that alternates between seven minutes of walking and running on a treadmill and three minutes of continuous strength-training moves for up to 50 minutes.

MIAMI

The Class Barton Biking

Where David Barton Gym ( davidbartongym.com)

What it is A one-hour session, during which you'll power through a biking interval and grab a pair of dumbbells to do a few sets of arm or shoulder exercises; then repeat until you've strengthened your entire body and burned more than 500 calories.

CHICAGO

The Class Chaos

Where Equinox ( equinoxfitness.com)

What it is A boredom-busting hour and a half of cardio drills and strength-training exercises. The class also in-volves make-believe, such as sprinting across the "street" (a.k.a. the studio) when you hear a "horn" (whistle) to avoid a "car" (stability ball). You'll work your body and mind in a variety of ways--kind of like you do in real life--and have a blast in the process.

NEW YORK

The Class Bin Zhou

Where New York Health & Racquet Club ( nyhrc.com)

What it is In 45 minutes you'll meditate and do breathing exercises, then perform a series of tai chi and qi gong movements and isometrics, such as holding a deep squat. You'll get a low-intensity cardio workout, but the focus is more on relaxation and increasing energy than on blasting fat.