Bulk up on your lean muscle mass at David Barton's new Astor Place gym.Photo: Courtesy of DavidBartonGym

Physique 57; 161 Avenue of the Americas, at Spring St.; 212-463-0570
This dance-inspired workout adapts classical ballet moves to improve your flexibility, core strength, and balance. But unlike the regimen of traditionally trained ballerinas, this 57-minute class incorporates free weights and exercise balls along with the ballet barre. The spot requires advance reservations and enforces a strict cancellation policy (no-shows lose their $35 deposit), providing ample motivation to stick to your workout routine.
$545 for 22 classes (regularly $545 for 20 classes); 1/1–1/31.

Boot Camp
Gold’s Gym; 250 W. 54th St, nr. Eighth Ave.; 212-307-7760
Gold’s 60,000-square-foot midtown location touts 60 group classes a week, including the winterized version of its popular Brooklyn Bridge Boot Camp. Participants undergo a rigorous circuit-training routine four times a week that includes weights, jump ropes, and interval cardio. Bonus for frequent travelers: Memberships are valid at any of the chain’s 650 locations worldwide.
$1,099 for two years (regularly $829 for one year). 12/1—12/31

Manhattan Plaza Health Club; 482 W. 43rd St., nr Tenth Ave.; 212-563-7001
While novice climbers navigate the more forgiving beginner routes, expert climbers can tackle difficult courses on the monthly redesigned wall or through the bouldering cave. The Learn to Climb Package ($100) includes an orientation, a month of free equipment rentals, and use of the climbing gym.
$70 per month, with a waived registration fee (regularly $195).

Ice Skating
Chelsea Piers; West Side Hwy. at 23rd St.; 212-336-6666
Get hyped for the Winter Olympics by joining Sky Rink’s Skating School, a weekly adults-only class on Monday nights. All participants begin with a fifteen-minute warm-up to music, then break into various skill levels for a 30-minute lesson. Beginners learn basic techniques for improving posture and balance, while advanced skaters attempt scratch spins, toe loops, and salchows. Classes wrap up with 35 minutes of free skating.
$35 per class (four-class minimum); twelve classes for $350 (originally $420). Rentals are included.

McBurney YMCA; 125 W. 14th St., nr. Sixth Ave; 212-912-2300
Since opening in 2002, this spacious Union Square mainstay has been trumpeted as one of the top locations of the eighteen citywide YMCAs. Three of the seven lanes in the pool are roped off for laps, while adult Aqua Aerobics classes help burn calories and build endurance. Use of the steam room is included in a membership.
$88 per month, with a waived registration fee from 12/26 through 2/1 (regularly $125).

Namaste Yoga & Tranquility Center, 336 Grand St., nr. Havemeyer, Williamsburg, Brooklyn; 718-874-3484
Yogis daunted by intense Bikram and vinyasa studios find their way to this intimate Williamsburg space, where the focus is on spirituality and controlled breathing. Learn basic positions and yoga tenets at the once-a-week beginners’ series, which begins January 6 and runs through the 27th. In the spring, more advanced classes are conducted in the spot’s sunny backyard.
$60 for the four-class Beginners Series if you register by 12/21, $65 after.

Weight Training
DavidBartonGym, 4 Astor Pl., nr. Broadway; 212-505-6800
The newest addition to DavidBartonGym’s muscle-building empire offers 40,000 square feet of strength-training space filled with machines, free weights, and personal trainers. Starting December 9, look out for the new WOW (Women On Weights) class, a group-workout program that hones in on exercises specifically designed to boost metabolism and fat loss.
$125 per month, with a waived registration fee through 1/31 (regularly $400).