After 26 years, I am still practicing what I preach.

Far too many times over the next 12 to 15 years, it was brought to my attention that people who followed my exercise guidelines exactly but ignored their diet, their weight and their cigarette smoking had heart attacks at age 55.

Now I say that if you run more than 15 miles a week, it's for something other than aerobic fitness. Once you pass 15 miles, you do not see much further improvement.

If you look at body fat, it seems to increase with age, even though your weight does not. That's a physiological fact of aging, they say. Heck it is. It is an adaptive effect of aging.

[Walking's] overwhelming advantage is that it can be done by anyone, anytime, anywhere-and it doesn't even look like exercise.

Since then, I have not missed five consecutive days in getting some type of aerobic exercise, mostly jogging.

I used to think that it didn't make any difference how far you ran if you had a good, strong musculoskeletal system and no underlying cardiovascular problems.