Three sisters share a family sport:
A non-stop race
The oldest is fat and short
And trudges slowly on
The middle sister's tall and slim
And keeps a steady pace
The youngest runs just like the wind,
Speeding through the race
"She's young in years, we let her run,"
The other sisters say
"Cause though she's surely number one,
Shes second, in a way."
who are they?