not only do you coast alot on a freewheel, but brake alot too, on a fixie that is usually done with the legs which takes lots of effort as well

lots of racer type roadies dis fixed gear then find out the hard way that a regular fixie rider is likely to be in very very good shape despite what they may be riding or wearing, kind of ironic really, so many roadies look for any way they can equipment wise to get more speed and reduce the work they have to do to go faster yet the easiest way is just get a better workout and make more power