I pretty much just do it regardless of size.
Right now my interests revolve around my volunteer work, my gardening, and my kid.
While obese I finished my degree, got married, raised money for charity (biggest was 15K raised under MY leadership-- woot!) and did two half marathons as a walker. I did a whole bunch of other things too like animal rescue or teen work.
But if you want to pin me down to something I want to do but am kinda holding off on... zip lines. They look like fun, but I'm scared of heights! So I kinda want to be lighter before I go there in case I fall. Makes no sense at all, right? But there you go.
I am not always a rational being. LOL.