How can I separate wrist and elbow motion?

When attempting reverse dart wrist picking, I have noticed that I subconciously add in an elbow motion when playing at faster speeds.

This would be fine, however I feel like the elbow motion makes me lose control of the pick a bit, and playing at those faster speeds is often inconsistent for me, and I notice my elbow tensing and fatiguing

How can I learn to separate these motions in order to either play with ‘pure’ wrist or to be able to control when I add in an elbow motion?

I know this is more of a trick-yourself-into-doing-something kind of thing, and there isn’t a set way to achieve this, but I am wondering if anyone has any tips or suggestions?

Thank you!