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.