I have been suffering from IT band problems on my outer knee, which I'm pretty sure were caused by raising my seat height too much. I raised the seat on the advice of a friend who said that a higher seat gives more power in each stroke.

By trial and error over several months I have found a (lower) seat height that seems to be acceptable, but I still get occasional twinges if I cycle a lot, so I suspect it's still not quite right.

Is there a well-understood way to correctly determine the best height for a bicycle seat? Are there factors other than seat height that are important to consider?