I’m confused ..
They are on bicycles going as fast as they possibly can.
Not pedaling isn’t an option, the bicycles are direct drive and the only way to stop is to take your feet off the pedals and coast?
But the pedals are still moving so you can’t actually put your feet down unless you jump off the bike.
They apply reverse pressure on the pedals to slow down. It is kind of like engine braking in a car. But they basically coast to a stop. And their feet are secured to the pedals with a mechanism similar to the one used on snow skis. Unlike road races they start fully clipped in with a person holding them upright until the bell sounds to start the race.
Velodrome race are short and at very, very high speed.