I just watched the video of the women's 400 meter where the winner dove across the line. My take....looked like she was leading right up to the time she began to fall and simply fell/dove at the finish.

Its totally legal.

A well known runner stated that everybody knows the fastest finish is running and just leaning at the last at the tape.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.