Hey everybody,
I am closing in on Mastery for FL PE1 and noticed, that I start with my back completely flat on the ground. After a few sets, my lower back starts to arch slightly (not much, but still). I can complete all sets with the slightly arched back, but not with my back completely flat on the ground.
I was wondering, if it is necessary to be completely flat to demonstrate mastery? There is nothing particular about the lower back in the form tips and the other videos.
Cheers and thanks for your help,
Patrick