You need: To bond with your crew.
Try: MasterJay’s roller-skating dance class. You’ll relive that happy-tired, damp-haired feeling of your youth, except you’ll be targeting all those (now soft) lower-body muscles. Forget falling; beginners start slow. And don’t forget to BYO skates (in-lines not allowed).
What it works: Glutes, quads, thighs and calves.
Details: $12. Tuesdays; 7:30 p.m. for beginners, 8 p.m. for intermediate and advanced. MasterJay Moves Dance Studio, 1807 Chestnut Street, studio A, 215-564-2575, masterjaymoves.com.
You need: To be outdoorsy (but inside).
Try: Rock climbing at Go Vertical, the biggest climbing gym of its kind on the East Coast. Beginners can sign up for a two-hour intro class. And with 250 climbing routes, even pros don’t get bored.
What it works: Pretty much everything. This full-body workout tones and trims you quickly.
Details: $65 for a beginner class; $13-$18 for a day pass. 950 North Penn Street, 215-928-1800, govertical.com.
You need: An unexpected night out.
Try: Salsa dancing at Brasil’s. Thanks to the numerous Latin men looking to dance (and yes, they want to dance), you can have two left feet and still work up a sweat. Head there at 9 p.m. on Wednesdays, Fridays or Saturdays for free (with cover) salsa lessons before the party starts.
What it works: Your heart and brain—and it torches calories.
Details: $5-$10. 112 Chestnut Street, 215-413-1700, brasils-nightclub-philly.com.
You need: To get some fresh air.
Try: Ziplining at Spring Mountain Adventures. The heart-pumping thrill of zipping across snowy treetops, climbing boulders, wrangling with cargo nets, running across bridges and rappelling down walls is so much fun that you won’t even realize you’re burning mega calories. (Think upwards of 800.)
What it works: Legs, arms, abs and heart.
Details: $49-$79 per person. 757 Spring Mount Road, Spring Mount, 610-287-7900, springmountain-adventures.com.
You need: A healthy shot of adrenaline.
Try: The beginners’ aerials class at the Philadelphia School of Circus Arts. This eight-week course will turn your idea of arm work upside-down as you swing from the trapeze, climb rope, and twist in colorful fabric.
What it works: Stomach, shoulders, arms and back.
Details: $162 for an eight-week course. 5900A Greene Street, Germantown, 215-842-1040, philly-circus.com.
You need: To relieve some stress.
Try: Boxing at Joltin’ Jabs. Joey DeMalavez has trained everybody from Charles Barkley to Q102 DJ Rocco Cima, and his nonstop drills on the bag tighten and tone underarm flab and pull in the most defiant waists.
What it works: Biceps, triceps and abs, plus it’s a killer cardio workout.
Details: $135 for a six-class package. 4313 Main Street, Manayunk, 215-482-4802, joltinjabs.com.