Sex Positions That Double as Exercise

Scissors

According to Britton, the scissors position is the least strenuous of all -- there's no suspending of body weight, and it generally makes for gentler and slower penetration (which would explain why it's often recommended for pregnant women). "Scissors is for when you're tired, not for being an acrobat in bed," she says. Still, that's not to say you won't still be engaging muscle groups.

With your legs intercrossed with your partner's, there's limited movement for both the man and women, so a lot of inner-thigh strength and core stabilization will be at work. "When you squeeze your inner thighs, the core will naturally contract as well," Berman explains.