with the vein's with the valves in everywhere , yes, it's because they've got to somehow or other, you've got to somehow or other get the blood back up to the heart again, it's not under pressure is it any more, cos it's lost a lot of its pressure and the way it gets back to the heart of course that is it's lying alongside the bones and the arteries and as you're walking around, okay, the arteries are still having the pressure working, the muscles are still working and the vein lies next to it and the blood is able to be milked up, it's milked back up to a non return valve, that shuts off and it can't drop back down any further and the next bit does the next bit up, okay, and then that shuts off and eventually it gets back to the heart and the capillaries  what will that look like when it's bleeding?