This is a very efficient coordination movement to practice a press up to handstand. It also helps to practice the core structure and reduce the curve in handstands with a banana shape. There is also a variation using a pilates ball that can be a bit easier in the beginning. To understand how to pile up the structure of the body, you don’t need to do a lot of repetitions. It is better to pull slowly and observe what muscles are engaging and get how to coordinate the movement.
Another variation is to hold the plank position, then slide the legs, pull the pelvis up and hold again in the pike position contracting the lower abs.