How to properly change scale of blender model and it's rig?

I am having trouble changing scale of a model in blender and it’s rig after already animating it. I tried to change and apply it in blender, but the result I get in unity is the following:


My character gets completely streched and as it seems rig’s scale is the thing that I have trouble with.
I hope you can help me, thank you.

(Im not a blender user)

If you are scaling the character entirely (not just sections of the character) can’t the scale factor in Unity accomplish this - without messing up the rig?