I’ve been working on the planche, a difficult gymnastics trick considered to be one of the most challenging to achieve. Dragon Door has a very excellent article on conditioning for the planche pushup called Building an Olympic Bodythrough Bodyweight Conditioning by Christopher Sommer.
My progression has me starting to do the “advanced tuck planche” for about 15 seconds, while I can do a more basic ball planche for 60 seconds. I *do* work the planche pushups with my feet on the floor, but it is dramatically harder to lift your feet off the floor because in order to get that leverage your hands really have to be down at or below your hips. That makes the strength involved by your anterior (front) deltoid, and pectoral muscles, as well as some triceps strength to be on the extreme end.
Here’s a great YouTube video of a guy doing a few planche pushups properly.
If anyone has access to resources explaining how to calculate the strength of gymnastics and other bodyweight conditioning exercises, when changing the angle or leverage, I would be very interested in this. Please contact me!