As I travel the country talking about osteoporosis, my final emphasis is on tools for preventing onset or progression of this "silent" disease (because it is painless) which kills more women than breast cancer. That inevitably leads to a discussion about the two kinds of weight-bearing exercise--lifting weights to increase the strength of muscles that pull against bones and cardiovascular exercise that bears your weight as you strike your foot on a hard surface. The latter excludes swimming, bicycling, elliptical machines and rowing which happen to be very fine exercises for reaching optimum fitness. Nevertheless, if you want your bones to be strong you need to be walking, stepping, jumping or running for fitness.

Most the people in my audiences opt for walking. What they don't realize is that a casual walk, though better than nothing, is not a bone building experience. It's the strike of the foot against the pavement that you get only from brisk walking that translates the force up your leg and into the vulnerable hip and spine.

Walking also improves your mental well being. Danish philosopher, Kierkegaard, said, "Above all, do not lose your desire to walk.". Every day I walk myself into a state of well-being and walk away from every illness.

Nietzsche, the German philosopher went further (if you'll excuse the pun). He wrote, "All truly great thoughts are conceived while walking."

These philosophers were describing another, also important, kind of walk known as the constitutional because they were "good for your constitution"--your overall well-being, body and mind. These are walks that are closer to meditation because they are a temporary vacation from our compulsions to be humans doing.

I walk often with friends. We talk about the mundane and important issues as we maintain a pace brisk enough to make us slightly breathless. I like to remind myself that I've put myself in the good company of Gandhi, Darwin, Emerson and many creative (and long lived) people throughout history who took constitutionals often. You should too.