Originally Posted by Klay
I'm pretty sure it would be "affect".
You want to "affect" the action to bring about the desired "effect".
Here is an example from the interweb:
"Gender may affect
the action of garlic oil on plasma cholesterol and glucose levels of normal subjects."
Klay's use of effect, as a verb, is correct.
A change that is a result or consequence of an action or other cause.
Cause (something) to happen; bring about.