What Causes Frequent Heaviness In Arms And Legs?

im experiencing frequent heaviness of my arms and legs..and i cant walk faster and stand faster.and im experiencing difficulty of raising my legs because it really hurts when i do, with my arms, its heavy, and i cant hold something enough to let is stay with my hands, if my arms are heavy, the same goes with my legs, and that happens in one day only, what is happening to me doc?