I am coach of Greater Boston Track Club, wrote the history of the Boston Marathon, ex-produced the Boston Marathon Documentary and worked with Jack Daniels at Nike while he was gathering data for his book. My wife edited the first edition so I read every word at every stage and spend hours talking with Jack about running and the physiology especially as it related to product design which was my Nike job in the early 1980s. We were testing air shoes, strange plastic inserts that never made it, and even carbon fibers that we could not get to work with the foam available at the time. Jack was at the forefront of all this seeking measurements from testing not opinions based on authority or marketing dreams. His objective was to collect data and base decisions upon that and not on wishes, hopes, and anecdotes.
I would make shoe prototypes and Jack would test them on runners to see if greater efficiencies resulted. We did that over and over. Others are doing the same scientific investigations now. If as we all wish, Jack were in his prime, he would write another book based on more decades of research. It would be different. So read his book, read all the others, learn from your experience, and apply that where the intelligence leads you.
I am so much looking forward to Jack's 90th birthday and so much appreciate his intelligence.