# How fast would someone have to run to run over water?

I was thinking about Flash, the superhero, or the little boy in the Incredibles.

There is one Yahoo answer that doesn't answer a lot. Especially, I don't think surface tension would help a lot for a human to run over water, I think one would have to build on the inertial effect of the water.

There is one empirical approach based on figuring out the speed at which bare-footed water skiing is done, but I wasn't able to find a decent number. Still the difference may be that a hypothetical runner would have to propulse herself over the water, which may or may not make the thing more difficult.

Hence, I raise the question here.

• One problem I suspect will come up when comparing to bare-footed water skiing is that bare footed skiing pushes water in the direction of motion, creating a high pressure - and higher density - area making it easier to get the required thrust. Whereas when running the water is pushed opposite to the direction of motion, creating a low pressure area ahead of the test subject and making it even harder to get the required thrust. When running fast enough we might be able to jump over the low pressure area, but we will never get a high pressure area to land on. Nov 21, 2020 at 19:33