The book chapter is about form for running fast, but most of the comments are about form for training. In terms of injury prevention, I'd agree that the latter

The book chapter is about form for running fast, but most of the comments are about form for training. In terms of injury prevention, I'd agree that the latter is important, but the book chapter doesn't have a lot to do with this. All the pictures are of people running better than 5 minutes/mile, with some probably running faster than 4 min/mile. But almost all running injuries are the cumulative effect of lots of slower miles, run at 6, 7, or 8 minutes/mil, or even slower (though the difference between 6 min/mile and 8 min/mile is pretty significant). Good form at those speeds is markedly different. For fun, try to find footage of Kenny Moore running. Looks absurd, so knock kneed, but terrifically fast in his day.