You're lifting those barbells for strong muscles. You're walking around the block or running marathons or doing 1,000 jumping jacks every day for a stronger heart. Hurray!

But what are you doing for your mind?

Research shows we need to keep our brains stimulated as we age. If not - well, we're not going to tell you because you probably won't remember anyway.

Instead, we of the problem-solving, nip-potential-problems-in-the-bud brigade, are going to help you along with five ways to keep your brain stimulated.

1. Don't be so predictable. When we get into a routine (a k a rut), aarp.org tells us, our brains adjust and aren't as stimulated. To offset that, try taking a different route to work.

2. Pretend it's "Opposite Day." Brush your teeth with your left hand if you're right-handed. Southpaws, use your right hand to move your computer mouse.

3. Learn a new word every day. Practice using it without saying, "I think this is the right word," and giggling. Get it e-mailed to you from m-w.com.

4. En EspaƱol tambien! No, we're not talking about learning what pollo or queso mean on your favorite menu. Branch out - try studyspanish.com instead.

5. Make time to play. Do a crossword puzzle. Play Sudoku or click on prevention.com/braingames for fun ways to stimulate your cerebellum, cerebrum, cellophane ... whatever that thingie inside your head is called.