Why do keepers always come out to warm up

Before the rest of the team? This has always baffled me. I've asked people in the past and nobody has ever been able to give me a credible reason.

Any ideas?

 

Both keepers have to be warmed up. It's not like outfield where they can warm up together. Each keeper will be put through a set of exercises, which can then be duplicated.

That's my idea

 

Get a bit of proper GKing practice in before rest of team come out and start wanging half a dozen balls at them.

That's my experiences anyway.