Work off the last of the summer barbecues at Attune Holistic Fitness, where for $45 (normally $100 to $150) you can take a Functional Body Movement class that targets pretty much every muscle group. The one-on-one session lasts an hour, with a personal trainer coaching you through various exercises using kettlebells to tone, strengthen, and condition. 1551 Second Ave., nr. 81st St., 212-288-0920; through September 30.