This week’s (not) parkrun Progress Report is the first of a two-part series looking at one of my athletes, Pip, and her 5K time trial progression.
This is Part 1 — her initial benchmark run from 3rd March 2026, where she ran 32:24.
At first glance, it looks like a solid effort.
But when you dig into the data, there’s a very clear lesson sitting inside this run.
She didn’t run out of fitness — she spent it too early.
The run at a glance
Here’s how the run unfolded (mile splits):
- 1st Mile – 9:45 (6:04/km)
- 2nd Mile – 10:17 (6:23/km)
- 3rd Mile – 11:14 (6:59/km)
- Final ~170m – steady finish
This tells a very clear story:
- fast start
- steady slowdown
- progressive fatigue
The start: strong… but too strong
The opening mile at 9:45 stands out immediately.
It’s not just a good start — it’s too good relative to what follows.
Because from that point:
- the second mile drops by over 30 seconds
- the third mile drops by almost a full minute again
That’s not just pacing variation.
That’s early overcommitment.
The cost of the first mile
Once you go out too hard in a 5K, the body doesn’t forget.
It adjusts.
And in this case, the adjustment shows up as:
- slowing pace
- declining cadence
- reduced ability to hold rhythm
By the third mile, the run has shifted from:
executing a plan
to:
managing fatigue
The heart rate tells the real story
Heart rate across the run:
- 168 → 167 → 165 → 164
That’s not what we expect in a well-paced 5K.
Normally, heart rate should:
➡️ gradually rise as the effort builds
Instead, it:
➡️ flattens and slightly drops
That tells us:
- the body couldn’t sustain the early effort
- output had to come down
- and the system was protecting itself
This wasn’t a push to the limit.
This was a run that became controlled by fatigue.
Cadence: the quiet giveaway
Cadence tells the same story:
- 87 → 86 → 84 → 83
A steady decline.
That means:
- stride is shortening
- rhythm is breaking down
- efficiency is dropping
This is what fatigue looks like in the data.
The middle of the run: where it slips away
The biggest shift happens between the 2nd and 3rd mile:
- 10:17 → 11:14
That’s where the run really starts to unravel.
And this is typical when pacing is off early.
The body is no longer working with you.
It’s working to recover.
The terrain: not the cause
Yes, the course had some undulation.
But:
- elevation gain/loss was consistent across all miles
- there’s nothing significant enough to explain the slowdown
So the key factor here is still:
Pacing — not terrain.
What this run really represents
This isn’t a bad run.
In fact, it’s a very common first benchmark.
It shows:
- willingness to push
- strong intent
- and a lack of experience in pacing a 5K
And that’s completely normal.
Why this is actually a great starting point
Because this type of run gives us:
- a clear baseline
- a clear mistake
- and a clear opportunity
The opportunity being:
➡️ better pacing
➡️ better effort distribution
➡️ better overall result
The lesson
When you start a 5K too fast, the rest of the run becomes about survival — not performance.
What happens next?
This is where it gets interesting.
Because in Part 2, Pip repeats this 5K time trial four weeks later…
…and the result is completely different.
Not because she got dramatically fitter.
But because she learned how to pace the run properly.
Want help with your own pacing?
If you’re unsure how to pace your parkrun or 5K — or feel like you’re leaving time out on the course — I can help.
👉 Apply for your own parkrun Progress Report here:
https://qwik-kiwi.kit.com/parkrun_progress_report
Or if you want a structured plan to improve your pacing and consistency:
👉 Join parkrun Kickstart here:
https://www.coachraytraining.co.nz/signup/parkrun-kickstart
Ka kite anō — and I’ll see you in Part 2 (next week).