I have slowly been losing strength in my legs, if i walk too far they burn and then after i sit the burning goes to my feet and more or less feels like pins and needles.. Sometimes they go numb? I have just been checked this month for any blockage with a carotid sonogram, and it went well. So i am at a loss.. The Dr. said to walk more, but how can I do that with the burning and numbness.. I ve tried..