so i saw the wr run launch themselves around the map with explosives and they pretty much instantly get up instead of bouncing around the map. you can see it for example at 9:30 in the youtube video. does anybody know how that works?

In short, spam B. Pressing B will make you ragdoll around but if you're already ragdolling, spamming B until you enter the get-up animation (usually takes around 3 quick B presses) will stop your momentum and make your character stand up.