exercise while playing online? (no poker content)

[Skipbidder]

I'm getting fat. I'm spending my free time sitting on my ass playing poker. Good for my wallet, bad for my waistline.
Anybody manage to do any exercise while playing?

I've just started lifting handweights while playing. This is doable, but doesn't get the heart pumping.

I was wondering whether riding an exercise bike is plausible.
Anyone trying anything like this?
Other ideas?

Thanks.