(from the Foreword, titled "Walking Lessons") Walking lessons? You might think these are as unnecessary as eating or breathing lessons. Isn't walking a skill we learn around the age of one, pretty much master by two and then never forget. Not really. Children don't suddenly stand up and walk. Their first steps are lunging runs into the arms of waiting parents. They don't slow down much until their teenaged years, then soon get a driver's license and thereafter limit their walking to crossing parking lots or trekking home when the car breaks down. A few of us keep running after learning to drive. I was among those lucky ones that way. However, more than 20 years passed between my first formal race and my return to walking. I took that long to adopt walk breaks as good and necessary additions to what remains today a running-centered routine. I also freely confess that little more than half of the "run" time nowadays is spent running. Walk breaks come often, and some days pure walks replace runs. Pure runs are as rare as lunar eclipses. Walking hasn't replaced my running but has added to it. Walk breaks, the simplest and best type of cross-training, have extended my life as a runner. I happily stop to walk if it keeps me running longer - if not in miles, then in years.