How to make animation exclude specific axis of rotation?

Help and Feedback Building Support
1

I only want the Y axis of the rotation of the UpperTorso to be animated without affecting the X and Z but how?

image
image748×263 15.6 KB

2

needing help still. i tried everything i know

image
image426×798 25.3 KB

even with the weight being very low, the uppertorso is still being animated fully