He's second, in a way

I think it's been some time since I last shared a riddle. I just got this one, which isn't that hard, but I like it ^_^

Three brothers share a family sport:
A non-stop marathon
The oldest one is fat and short
And trudges slowly on
The middle brother’s tall and slim
And keeps a steady pace
The youngest runs just like the wind,
A-speeding through the race
“He’s young in years, we let him run,”
The other brothers say
“‘Cause though he’s surely number one,
He’s second, in a way.”

I already found the answer, but I'll wait till it's confirmed before posting it. I just hope I won't forget! :P

Edit: Answer below.















Answer: The hands on a clock (hour, minute, second).