Many questions in the beginning, sorry.
This time, how much effort should I put into each mastery.
For instance, if I can master the hollow body hold for stated time using say 70% of my strength is that ok or should I strive to use full contraction and not be able to pass yet, meaning using more force than necessary for the hold.
The hollow back hold is another example, as I see it it can also be performed with different effort depending on how much arch you put in your body.