Not the person you're replying to, but I have some sources. The best consistent source I've found is Alex Hutchinson. He reports on scientific studies and tries

Not the person you're replying to, but I have some sources. The best consistent source I've found is Alex Hutchinson. He reports on scientific studies and tries to sift the wheat from the chaff. Quick search found this one on stretching [1] from him. Foot strike and mechanics is a much more complicated area AFAIK. He also wrote a fantastic book on the state of sports science "Which Comes First, Cardio or Weights? Fitness Myths, Training Truths, and Other Surprising Discoveries from the Science of Exercise" [2] which I highly recommend if you're interested in hearing about the source studies (and their limitations). [1] http://www.runnersworld.com/sweat-science/should-you-stretch-before-running http://www.runnersworld.com/sweat-science/should-you-stretch... [2] http://www.goodreads.com/book/show/11115311-which-comes-first-cardio-or-weights http://www.goodreads.com/book/show/11115311-which-comes-firs...