Question Rig Gradually Deforms

Hey there!

I have an odd problem I'm trying to diagnose.

So over time, my character shrivels up, the bones just move inwards.

I have character joints and Rigidbodies on most of the bones. The Rigidbodies are set to kinematic with Continuous Speculative collision detection and interpolation.

Picture attached:

 

Update: I disabled my scripts that drive any sort of upper body animation / ik.

So now the animation is just driven by a blend tree, pretty much only animating his legs to run / walk / strafe.

And now, only the legs are deforming:

 

Update:

Deleting the Rigidbodies fixed. Why though? They're all set to kinematic?