Yeah, I tried that. Didn't work for me. I'm too clever for my own tricks.
The idea is that I need to build tolerance for that task. If you keep at it, those 5 push-ups will become so easy that you will feel compelled to do more.
If it's not working, then there's another reason behind the resistance. Maybe what you're trying to do feels pointless. Try to notice your feelings and internal dialogue when you're trying to do that particular thing.
You can start by doing something you actually LIKE doing - no tricks.