|Nick Willis leads the 2013 TC 1mi|
This week, Twin Cities in Motion announced that the 2015 edition of the Twin Cities 1 Mile will be run on a new course heading north on Hennepin Avenue through downtown Minneapolis, instead of the historic course down Nicollet Mall. The motivation for this change was construction of a new light rail line that crosses the Mall, with trains that run every few minutes—far too frequent to be able to get a full wave of runners across quickly.
The old course was flat and very fast, and with its very generous prize purse, the elite wave attracted several extremely fast milers. Because of stormy weather, the race was canceled at the last minute in 2014, but in 2013, Nick Willis set a course record of 3:56.1 in 2013 for a cool $10,000 bonus, and five other runners broke four minutes.
A new course, but the same record
In a recent interview with Minnesota running blog Down the Backstretch, TC 1 Mile race director Jeff Decker clarified that, even though the course has changed, Willis' 3:56 (and Sara Hall's 4:30.8, run in 2011) are still considered the "event records," so to earn the $10,000 record bonus, these are still the marks a runner would need to hit.
Which brings us to the new course. The new route up Hennepin Avenue has no turns to mention, but it does have a noticeable uphill in the first half mile or so. Down the Backstretch provided a handy chart comparing the elevation profile of the old and the new course. Can we use this to predict whether the course will be faster or slower, and what kind of performance would be necessary to break a course record?
In fact, we can, as long as we make a few simplifications. If we can make an idealized model of each course, we can compare their relative "fastness." As you can see in the chart above, the old course fluctuates a bit, but never gains nor loses more than ten feet. Because of this, I'm comfortable treating the old course as if it were perfectly flat, i.e. no significant differences from an idealized "fast as possible" course.