San Francisco Summer is right around the corner, and Pop 5 favorite gym Crunch (various locations) just released its Fall class schedule — perfectly timed for any last-ditch efforts at sleeveless shape-ups. Here are four classes I suggest you try ASAP, and one you don't.

  • Diesel Michele at FitSugar introduced me to this awesome circuit-training class for short attention spans. Brief bursts of cardio are intermingled with strength training, so just when you think you can't stand to do another rep, you switch, and by the time class is over, you've worked every muscle group.
  • Ultimate Conditioning Similar to Diesel but with less cardio and more punishing lifting routine, Ultimate Conditioning feels like working out with a personal trainer. The instructors are attentive and motivating, yet you can make the class easier or more difficult depending on the weights you choose. I really like Andre, who teaches at the New Montgomery location (61 New Montgomery St., 415-543-1110).
  • Glee Club SF finally gets this dance workout class that New Yorkers have been gleeking out to since January. The 45-minute session serenades you with music from the TV show and hits on dance styles ranging from hip hop to salsa.
  • Chisel Just as intimidatingly named as Diesel, Chisel focuses on core strength training, with lots of balancing on stability balls while doing crunches and lifting weights. You might be sore for a week, but you'll also be seriously in shape.

For one class I wouldn't recommend, .

My experienced at the Stacked class at New Montgomery would have been comical had it not been utterly ridiculous. Described as a mix between classic Pilates, yoga, and weight training, this routine felt too unrefined, hard to follow, and ineffective. Plus, the instructor brought his dog to class, and she was running all over the studio. Talk about distracting. What classes would you recommend at SF's Crunch locations?