Hello Harriers, I hope you’re all well!

I wanted to do a blog to share my experience over the last 18 months and how the training mileage I have been doing has affected my fitness and the relationship between the two. I love to dig deep into the data and details of my runs, but I understand that’s not how everyone likes to do it. So maybe this won’t be a blog that will enthral all of you, but hopefully, you’ll find some of what I have to share relatable to your own running experience.

In December 2021, after a few years off from any running (I had previously been a 19-minute Parkrunner in 2019), I had decided to get fully back into running, with the goal of getting as fast as my body will let me over various distances.

I started by running a couple of KM’s a few times a week at a high effort to try to get the most bang for buck out of the time I was investing – and this did get me so far.

After a month or two doing this, I knew that the best way to progress was to increase my mileage while maintaining a degree of intensity.

This is where the balancing act starts: avoiding injuries.

The basic formula is essentially not too complicated – run more to get fitter, but as you do that, your body often cannot keep up with the enthusiasm you may have for running progress, and you will need to increase your mileage and/or intensity at a low enough rate that you can sustain consistently over a long period of time without suffering injuries to see the best developments in fitness. This has been my goal, and I have been very interested in finding out the relationship between Mileage vs Fitness and whether the old saying that “Mileage is King” is really true, or at least whether or not it helps my endurance over the distances.

So, using my own body as the guinea pig, I set out to come up with some data to measure this. My approach has been to have one fast interval session a week, one tempo session per week, one long run per week, and then the rest of the runs have been mainly easy mileage, which actually makes up the majority of my mileage. Normally, I have one rest day per week also. Feel free to add me on Strava if you’d like to see examples of weekly workouts and routines.

Yes, there are many variables to track, and I know it’s not a perfect measure, but I decided to use semi-regular Parkrun 5km maximum efforts to measure this at two locations, Malling and Maidstone.

Here are some graphs showing the Kilometers ran per month and Parkrun times from December 2021 up to July 2023:

As you can see from these graphs, I have steadily increased my mileage each month (unless a minor injury has occurred, and a rest has been needed), and this has enabled me to go from being in a 24-minute Parkrunner to a sub 17-minute Parkrunner.

Very roughly, the correlation between the graph shows the Km’s ran per month vs. the fitness measured by Parkrun time equated to:

  • 100km per month got me to sub 21 minutes.
  • 200km per month sub 20 minutes.
  • 300km per month sub 19 minutes.
  • 400km per month sub 18 minutes
  • 500km per month sub 17 minutes.

This Dynamic will not go on forever, and there is more than one way of achieving gains in fitness, such as increasing the intensity or frequency of intense workouts, and as you start to reach the limits of time available and the body’s ability to recover, this high mileage approach is tailing off, and the returns will be diminishing. So consistency and a more tailored approach to each workout may be required to progress much more for me.

This will not be directly comparable for many of you as there are too many factors involved; however, I wanted to show you all that what I have found is steadily increasing your mileage while maintaining a mixture of intensities consistently can lead to big gains over time.

Please don’t look at this and think, “I’m gonna run as much as possible now” without taking the time to listen to your body each run to assess if you need to change today’s workout to something easier or even an extra rest day, as the biggest limiting factor we all face is the dreaded injuries and niggles that can be so hard to shake. So if in doubt, go easier or shorter to be safe. And of course, if you are in need of advice on how you can draw up weekly/monthly running ideas to get to your goals or even maintain them longer-term, feel free to approach any of the coaches, captains, or runners you see at the club regularly, as we can help point you in the right direction to get you running down the road to success, in whatever form that may be for you. So, is Mileage king?

Not definitively, but it’s certainly part of the Royal Family…

See you all soon,
Lee Sander-King.


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