Where you see a broken physics engine, I see the Nordic space program. 

The interesting thing about this - at least for me, and from what I’ve heard - is why exactly this happens.

Basically the physics engine Skyrim uses turns any additional damage dealt after death into motion. So if you had 100 health, and someone hit you for 101 damage, you’d fly a little bit further than if you were just hit for 100. Likewise, getting hit for 200 when you only have 100 would send you pretty far back. As far as I know, the “Fus Roh Dah” shout basically translates all (or 99%) of your damage into momentum.

So what happens here is basically the giants are just hitting you for absolutely astronomical amounts of damage, and you’re hitting the ground and then bounding back up. It’s such a weird string of events.

Astronomical