Dr Scott, you mention pacers in the marathons, how do you know someone is a pacer? Is there a way to identify them or is it just someone that has a group with them?
most races let you know they have pacers at their website and bigger races with expos will have tables where you can meet the pacers. In the Lincoln Presidential Half I did a few weeks ago there was a big poster board up with pictures and brief bios of all the pacers. Usually pacers will be holding up signs with the time they'll be finishing in or the pace they're looking to maintain.