Im not quite sure what the exersize is called but its the one where you have the weight on your shoulders and you stand up then move up and down on your tip toes. My question is about how safe this is mainly due to the presure on the back. I can now lift the whole stack plus more added on top and although I lift this with no problems, I did wonder how it effects the back. I already have red marks on my shoulders because of the weight.
Any advice ?