Backyard Ultra Analysis

Introduction

The backyard ultra (BYU) concept is a relatively new race format in the ultra-running world, with the first event taking place in 2011. Since then, the volume of BYU races around the world has slowly increased, although they typically maintain a down-to-earth, non-commercialised atmosphere.

The concept is simple. Each runner has an hour to complete a 4.167 mile lap (known as a ‘yard’ in BYU parlance). This target is very attainable for the vast majority of runners. Runners are then required to repeat the same lap on the hour every hour until only one runner remains. Run. Rest. Repeat. The last person standing is the race’s winner, with all other runners marked as Did Not Finish.

My own experiences of running BYUs have reinforced to me just how important it is to have a meaningful pacing strategy and approach to these events. Finding the sweet spot between controlling one’s pace to conserve energy versus maximising rest time between laps is the key. Have I found it yet? To be honest, I don’t think I have. I still feel that I am completing laps too quickly. Other competitors who are running slower than me are often lasting longer into the race.

I have seen competitors adopt a variety of strategies. Runners used to shorter formats typically run their laps faster than the majority. Some runners like to insert a fast lap every few hours to gain a lengthier than normal rest time. Others who struggle with running slower than they are used to will run fast over the first 3 miles and then walk the remainder. The strategy can also be influenced by the hilliness of the course.

This has led me to wonder if analysing results from previous BYUs can unlock insights into the optimal approach to BYU success, and what the factors are that either boost or limit performance.

Other strategic aspects such as mental approach and refuelling are also key but go beyond the reach of this investigation.

Analysis Method

Firstly, it has been necessary to collate lap-by-lap timings per runner from as many BYUs as possible. Individual lap times are recorded at some but not all BYU events. The most comprehensive source of these races is Webscorer. This data in most cases also includes the runner’s age and gender. 

The data has been collated from 25 separate BYUs and 1167 runners with results ranging from 1 lap to 47 laps. The dataset will be added to as further race results come on stream. If anyone reading this has further data available, please let me know at ian@onemoremile.run.

Some races record lap times exclusive of rest time between laps, for other races the lap time is inclusive of rest time between the previous lap and the latest lap. This has necessitated the removal of rest times for some races, so that the data is standardised.

Alongside the lap times, the elevation of the course has also been included in the data.

Data analysis has then been performed on the superset of BYU data, with the results and insights described below. The following factors have been assessed:

• Lap times

• Pacing variability

• Course elevation

• Age

• Gender

What is the Optimal Lap Pace?

Does the pace of a runner have an impact on their overall performance in a BYU?

Let’s look at the average lap time per runner plotted against the number of laps that runner completed, in the form of a heatmap.