I think this is the treadmill animation from the fist game, if it isn't a prerendered video you may be able to find the animation file and apply it to an object like a treadmill. Would be a cool mod.

The animation is there in the game, it just isn't scripted to a command that we can give. Tbh, it would look a little weird to see a girl running on the spot. The Bounce command is almost the same result anyway.