It's not just the treadmill that has defined this gym as the best place in New York for a sassy alternative workout. House rhythms in Nadia's Grooveology class can transform us all into underground club kids. Childhood dreams come true in this exotic milieu that combines a retro vibe and cardio attitude; it completely demolishes the monotony of traditional exercise. Firefighting; a circus class; martial arts with live drumming in The Matrix; cycling to karaoke; stretching to the blues; tribal rhythms; and every yoga class from Bikram to Jivamukti are available. We were 'crunchified,' but Mark's relaxation massage put us back into action for next week's Broadway dance series with cast members of Fosse. Everyone's a star at Crunch, but the show is very popular, so get there early to reserve a place.