I might be outing a few people here, so if I disapear...
I've noticed something, and I'm not sure if it's a coincidence or not. So I'll put it here until I have more time to do a bit more research on the matter. (however the hell I would do that is beyond me at the moment.)
Riders of recumbent bikes, are more likely to have "Aero-bellies", aka beerbellies, aka the midlife paunch. Now, I've not really delved into the the reasons why this would be, but I do have a theory.
(Here's where the lynch mob forms)
Recumbents can't climb. (Or so I've been told)
And since recumbents can't climb, recumbent riders avoid hills. This leads to less attention paid to the whole concept of power to weight ratio. Air resistance plays a larger part in workload on a flat road than rider weight does. It's only when the road turns up that the weight of a rider plays a significant role.
So, do recumbent riders have aero-bellies becuase they think that they can't climb and avoid hills, therefore what they weigh is less importants.
Do riders with Aero-bellies ride recumbents, becuse it gives them a reason (er, excuse) for not being able to climb?
I leave the question to the reader as an exersize.