They say that when starting to ride a recumbent you have to get used to using your "bent" muscles. But honestly I didn't notice any different at all except for that I was riding longer and farther than ever before and that my muscles felt all rubbery from the work out afterwards. When deciding on if I wanted to try switching to a recumbent or not, I tried the stationary recumbent workout bikes at the fitness center I was a member of and didn't really like them. For some reason the sitting position didn't seem natural and was very awkward. Fortunatly my real recumbent bike didn't have those problems.