I think this is pretty universal! I was in a PhD program for art history, so I spent way too much time in museums with other people who also spent way too much time in museums and we all had the same experience no matter what our level of fitness.

A couple of weekends ago I was working at a horse jumping event and my job was to go around with the photographer taking pictures in the sponsor tent. I spent nearly nine hours walking slowly that day and was nearly dead.

The only thing I can think that helps (temporarily) is to stop and stretch from time to time and then move fast for a while--jog in place or do some jumping jacks if there's no space to cover territory quickly.

Sarah