Using your brain keeps memory sharp.

Byline: Julie Sevrens Lyons

PALO ALTO, Calif. _ "Use it or lose it," barks Danielle Lapp, a Stanford trainer sounding as tough as any boot camp drill instructor.

Except Lapp doesn't concern herself with abdominal crunches or gluteal squats. She couldn't care less if our arms are perfectly sculpted or our buns are made of steel. No, what Lapp wants is for more people to tone up the one body part most of us have overlooked, she says.

It's time to exercise our mental muscles.

"Your mind is very powerful," says Lapp, one of the nation's leading memory trainers, who has taught classes on how to improve mental recall. And when in shape, the mind "can do things easily that you don't think you could."

But when was the last time you stretched your mind? Gave it a well-balanced meal? Treated it to eight full hours of sleep?

It's no wonder then that we misplace our car keys, forget doctor's appointments and overlook anniversaries. Memory loss has much more to do with our brains being …