Pah - Team bicycle all the the way.
Very therapeutic and won't shag up your knees!!
But seriously Team Something is the way to go, it doesn't matter what exercise takes your fancy, just so long as it gets your heart pumping and is either in a group or outside (swimming being the obvious...
Exercise.
For me I need to get my lazy, good for nothing endorphin's pumping.
Everything feels a lot better when a little weight comes off, and I improved on a PB.