Before we get started, I would like to position this article as one of several recent articles that sit at the intersection between data science and marathon running. In previous articles, I have focused on several technical challenges related to visualising marathon training and performance data. Here I shift focus to analyse (my own) recent marathon performances using some of the visualisation techniques discussed previously along with several performance metrics from the sports science domain. As such, this article provides a concrete example of my own explorative data science process, showing how relatively simple concepts such as (running) speed and effort can be used to explore more sophisticated contemporary physiological measures such as resilience and durability in order to better understand performance in the marathon. At the same time, it is worth noting that similar ideas are proving to be relevant in many other endurance domains such as cycling, triathlon, skating etc.
I came to running late in life. I started in my 40s. I have been able to complete the Dublin City Marathon (DCM) 8 times now — beginning in 2013 — and I have been fortunate to achieve several new personal bests (PBs) along the way, even as I have gotten older. My most recent effort this year (2023) was a new PB on a cool, wet, late October morning. I crossed the line in just over 3 hours and 10 minutes, beating my previous best (2022) by more than 7 minutes.
As a data scientist, I am very interested in learning from my race experiences and this year the scale of my PB was surprising and intriguing. I felt that a small PB might be on the cards — if conditions were good — but I was targeting a best-case finish of 3 hours and 15 minutes and 3:10 didn’t feature in my plans. Was this performance a simple matter of trying harder and running faster? Or were other factors at play? How did my pacing and effort compare to previous races and PBs?
In this article, I will consider several recent races to look at the interplay between my effort (heart rate, bpm) and speed (or pace, mins/km) as well as a more recent endurance metric known as durability [1], which is an emerging measure of physiological resilience, somewhat akin to what we might…