Typically you would drop the saddle height on the fixed by a cm or so.
I don't see how you can be tired riding a geared bike for a while. Once your body has adapted to it the driveline losses are minimal and the gear choice allows you to ride at a more optimal/efficient cadence, ie. once you're used to a road bike you should be more efficient/less tired/faster depending on what you want to do.
Typically you would drop the saddle height on the fixed by a cm or so.
I don't see how you can be tired riding a geared bike for a while. Once your body has adapted to it the driveline losses are minimal and the gear choice allows you to ride at a more optimal/efficient cadence, ie. once you're used to a road bike you should be more efficient/less tired/faster depending on what you want to do.