What Causes Heaviness In Legs?

Thank you doctor. My friend has had problems with her legs for 5 - 6 years and no one can find the reason for it. She explains it as her legs being heavy and can not move sometimes. She has fallen several times at home and when out walking. I'm worried for her...do you have any idea of what this may be caused by. She has seen several doctors. They have checked blood flow to the legs, etc but can not find the reason. Thank you for your time.