Answer:
If a man carried my burden, he would break his back. I am not big but leave silver in my tracks. What am I?
I am an activity dogs are very good at when a ball is thrown.
I run smoother than any rhyme I love to fall but cannot climb.
I run around the city but I never move.
Many people own a copy of me. Without me the world would fall.
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.