The SoulCycle ladies are willing to go bare for a cause

On May 17, SoulCycle’s star instructors, Biggest Loser sisters Olivia Ward and Hanna Curlee, and 500 New York women will gather in Union Square to work out—with their shirts off.

The Sports Bra Challenge was introduced by spinning instructor Jenny Gaither last year amid a summer surge of bare-your-body workouts.

Since then, Gaither turned the challenge into a full-fledged non-profit organization, the S.E.A.K Foundation, which supports healthy body image and self-esteem (especially among teen girls).

For foundation’s debut event, SoulCycle will set up 100 bikes in the north plaza of Union Square Park (across from Barnes and Noble). The day will include two classes on the bikes, a Vinyasa class, and Crunch’s drumstick workout class, POUND.

There will also be a “surprise” live performance. We’d like to nominate Lady Gaga, whose abs seem right for the gig, and who just celebrated her 26th birthday at SoulCycle in West Hollywood.

Class prices haven’t been announced yet, but all proceeds will benefit S.E.A.K. Registration begins April 16 at 9:00 a.m. at www.seakfoundation.com.

Will you be there, showing off your six pack (or lack thereof)? Tell us, in the Comments, below.