I am not sure if we posted something like this here - but anyways - this is a traditional Russian dance and its perform in such technique like the girls go sliding around like they are on ice. Just take a look - you can rewind to the
middle of the video to get into the action. They say its been done by special stepping one by one putting feet very close to each other. Here they dance "Beryozka" or "Little Birch Tree".