How do the walls of the olympic pools work as stopwatches?

Question

Do the walls react to the pressure of the swimmers' touching them in order to calculate the time?

Answer 1

they're touch pads. so basically when one comes into contact with it, the pad automatically records the time

Answer 2

The walls are like pads so that when the swimmer touches them it registers the times.  I BELIEVE that they MIGHT be heat sensitive but i am not positive

Answer 3

the wall has a huge pad sentative to presure as you said, its the most accurate way of doing it.  

Answer 4

when the swimmers finish they hit a pad that's pretty sensitive so the time is more accurate than people with stopwatches.

Answer 5

the walls have touch pads on them so they're able to get it every time the swimmer comes in for the finish or turn.

Answer 6

If you watch the underwater cameras carefully, the swimmers actually press a button when they finish.

Hope I helped!!! :-)