Pilates on the other hand is physical conditioning first and foremost -- and there's nothing quite like it. Its creator, Joseph Pilates, was looking for a way to rehabilitate injured soldiers after World War I. He developed an assortment of curious machines with names like the "Reformer" and the "Cadillac." Using cables and trolleys and unusual body positioning, Pilates exercises stretch and strengthen and are unique in their ability to encourage coordination between the muscles that stabilize the body.

Pilates techniques quickly became a hit with dancers, who found them a highly effective way to improve body awareness and alignment and promote graceful, fluid motion. Machine-based Pilates actually has more in common with weight training than with yoga since it involves moving against resistance (provided by springs) with the aim of overloading the muscles. In particular it resembles functional strength exercises such as squats or cable pulls. There's also a new form of Pilates, the Pilates mat class, which relies more on callisthenic-style exercises and stretches. This form is physically more similar to a yoga class though the emphasis is still on physical change rather than on spiritual development through postures and breathing.

The Choice Is Yours

Generally speaking, I think it's fair to say yoga is more about how it makes you feel while Pilates is about how you look -- how you carry yourself and move. So if you're looking for a limbering, rejuvenating workout that will provide as much of a lift for your brain as your body -- and you're not too concerned about building muscle --I'd recommend yoga. If you're interested in a more dynamic system of muscle conditioning -- or if you just want to try something new and different -- Pilates may be the answer.