Galen Rupp did an interview with Sarah Lorge Butler of Runner's World before Chicago. She got a few interesting nuggets out of him, including:
-He sometimes does long runs on a treadmill or on a 300m loop around a grass field. His explanation for the latter was that it helps prevent injuries. Maybe he does it on treadmills when the weather is bad or so he can run at altitude (he has a system in his house to reduce oxygen levels inside).
-He said he only had to modify two workouts to deal with his Achilles injury but says he feels fit.
-He still won't say how many miles per week he runs or give specifics on workouts but says he's done a long run "well over 26 miles" during this buildup.