“How Long is Your Marathon?”
It’s not a question from a well-meaning but under-informed work colleague or family member. It’s being asked the night before the Chicago Marathon, by one of the most knowledgeable running gurus on the continent. Combining a PhD in Geography and a passion for running, Sean Hartnett’s precisely detailed maps are the official course maps for the Olympics and major marathons around the world. To the last 20 years of Kenyan and Ethiopian world record holders from Haile Gebrselassie to Eliud Kipchoge, he is known simply as Professor Marathon.
The 26.2 mile distance is a uniquely precise number, but one that has become synonymous with the marathon distance since the 1908 London Olympics tweaked their course to accommodate the royal family. Since then (with certain exceptions, like the 2016 & 2017 Milwaukee Marathons), it goes without saying that a marathon in Boston, Berlin, or Beijing will be 26.2 miles. So why is one of the foremost experts in the field asking about how long an upcoming race will be?
The way Professor Marathon explains it, when a marathon is run on a relatively flat course on a day with ideal conditions, you’re in for a 26.2 mile experience. When you add in hills, humidity, or wind, the experience out on the course begins to feel more like more miles between you and the finish line. Preparing for that extra “distance” can make all the difference come race day.
Even the same course can mean a varied “distance” based on conditions year to year. The 2011 Boston Marathon featured a tailwind that aided runners on their point-to-point journey from Hopkinton to Boylston Street, making for blazing times and tons of lifetime PBs. It was a day about as close to 26.2 miles as you get at Boston. In 2018, monsoon-like rain, winds, and cold temps made the same race course feel significantly longer. American Des (Davilla) Linden finished 2nd in 2011 and 1st in 2018: her winning time was over 17 minutes slower than she’d run 7 years prior. The experience in Boston 2018 was closer to a 50k feel than a favorable conditions marathon.
This variable “length” of marathons shapes both our preparation and execution on race day. Some of the most effective methods for setting up for a positive experience late in the race comes from how you execute in the very early stages. Being overly controlled on pace/effort, increasing frequency of fuel/fluid intake, and keeping an internal sense of calm can mean your early splits are a few seconds slower, but your pace (and enjoyment) later in the race can be exponentially improved.
We apply a similar logic to other race distances, often to even further extremes when we look at ultramarathons. While your GPS may read a similar amount of miles covered, there’s a world of difference between the 100 miles covered at Tunnel Hill compared to Western States.
If conditions like heat, humidity, or wind are up in the air (like Boston often is), it can be beneficial to over-prepare and modify your execution. If you prep for a 28 mile race and find yourself on the starting line with calm winds and temperatures in the 40s, you may get the rare experience of finding a “shorter” than expected course that still counts as an official PR.