Few questions:
1. Is it ok to use a boxes instead, cause they dont have parallel bars at my gym
2. Are we suppose to land on the middle part of our upper arm (like the video), or do we land on our forearm, like most calisthenics/bar guys do?
3. What is our legs doing? would it be forward in front of us the whole time, keeping a hollow body, or can we bend our leg back?