Bends question

When you do semi erect bends or the sadsak’s slinky method, what side or chamber is being stretched? The inside of the bend or the outside?

It seems like the outside is being stretched but the inside is being crushed together. Which one is getting more expansion?

Thanks!

Well you’re supposed to do it on all 4 directions aren’t you so it’s an even workout. I think it’s obvious by sight the direction you go in you can see the bit being stretched. Basically you’re stretching the tunica outwards.