Depending on your age, lifestyle, and a host of other things, it could also
be a sign of peripheral artery disease. This is where the arteries begin
to plug up - very slowly, and the extremities are the first to be
noticeable. If this happens mostly in your legs and feet it is called
claudication, a subset of PAD. If your legs cramp or get very sore while
walking any distance (generally, but not limited to, the calves), it could
easily be claudication. Diabetes is a heavy contributor to this condition
and half of the Americans who have diabetes, don't know it.
There are some very modern techniques for dealing with these conditions.