[bluecalm]

I am familiar with those studies. Still I would like to see the footage of actual elite runners heel striking. I watched quite a lot of it and haven't seen one. My suspicion is that those elite heel strikers are just midfoot strikers in shoes with pronounced heel.

As to your studies: the first one doesn't include elite runners so isn't very relevant. The other one looks like meta analysis of other older studies. I am not arguing that heel strike is definitely wrong btw I am just yet to see an elite runner using it. My intuition is that it's mainly about striking the ground when your foot/leg already moves back. It just doesn't feel natural to do it heel first at least not to me.

I am not sure why you think sprinting is about forcefully driving your foot into the ground btw. It's the opposite. It's about lightly "brushing" the ground to "push" it horizontally behind you. See for example this footage: https://youtu.be/RD_TtokBUKc

The heel doesn't even hit the ground. It's the same when you look at the elite 10k or marathon runners although there heel usually lands on the ground for a while, especially in marathon: https://youtu.be/V4L113lP_54

With those new Nike shoes it almost look like heel strike because of the heel to toe drop in the shoe.

[slibhb]

How fast you sprint is a function of how hard your feet hit the ground. They aren't "brushing" the ground at all. I didn't say the heel hits the ground while sprinting.

edit - Googled for 30 seconds and found this video: https://www.youtube.com/watch?v=andAaS6Lyc8

The first runner he talks about uses a midfoot strike, the second uses a heel strike. They're both elite marathon runners.

As I said, my conclusion from having looked into this is that this debate is folk science. It might be correct but there's no compelling evidence.

[bluecalm]

How fast your sprint is a function how much backward force there is. You don't drive "down", you drive back. Try driving down and you will see it's impossible to do with any kind of force without the heel touching the ground.

Thanks for the video. The guy in the assistance crew is in fact heel striking. It's not classical extend your leg to hit the ground and roll novice runner kind of heel striking as his leg already moves back and his knee is already bent when he hits the ground but he does hit the ground with the heel first.

I wonder if it's because of the shoes. I don't think he would do that in flats/track race shoes.