Swollen fingers during exercise??

[swiperfox]

Just been on a 5k walk - have been doing it for a week but this morning when i got about half way my fingers really swelled up - very much like they did when i was pregnant!!

Does anyone know a reason or meaning for this?

Oh I get this when I do distance running, I was told once what it is, but being thick I've forgotten, sorry, Its nothing to worry about tho!

I'm sure someone has spoken to me about it before as well but i've completely forgotten!!
Can't be that important!!
Am intregued though......

This might be of interest

perfect - thank you!