I notice that sometimes when I am putting my heels down and really working on keeping my weight in them, I get numb toes/feet. It isnt very comfortable and I sometimes have to stop and wiggle them to try and get some blood circulating.
I wonder if I am over extending... but this happens when the stirrups are two short, just right, or two long. So Im not sure. I may also just have poor circulation in that position.