Here is a trivial proof of the former: take an elite biped marathon runner on foot vs an older marginally in shape biped like myself on a bicycle, and on my bic

Here is a trivial proof of the former: take an elite biped marathon runner on foot vs an older marginally in shape biped like myself on a bicycle, and on my bicycle I can beat the elite runner quite easily. Another way to model it is I can quite easily maintain 10 MPH without much if any sweating on a bike trail, but on a calm hike with the kids on the same trail I struggle to achieve 3 MPH average.