Scuddy Running 

The urban sport of running to the bathroom naked either in the middle of the night or just before you go for a shower and trying not to get caught.

It is a mainly Scottish term scud meaning naked in Scottish slang.

"It was 4am and I ran into my mum when I was scuddy running to the toilet".

Scuddy Running by Kirst-ehhh June 20, 2007