The single run that predicts running injuries
Daylight savings and running season
Kia ora! Yes yes — daylight savings is here! Always an exciting time of year, because it means summer is on its way (my favourite season).
On my usual commute run home earlier this week, the sun was shining and the footpaths were full of runners — great to see.
We’ve been on a bit of a “run” of running topics lately (pun intended). For our non-runners out there, don’t worry — we’ll shift gears soon. The reason we’re focusing on running right now is because we’re seeing a flurry of running-related injuries in the clinic. With the Auckland Marathon events coming up (including the Half Marathon and the 11km Traverse), we’re helping people get back on track.
Why injuries happen
These injuries tend to come in cycles — and this time of year is always busy. Classic reasons include:
Ramping up mileage too quickly
Increasing training frequency too quickly
Increasing pace too quickly
Suddenly starting hill repeats or interval training
New shoes (and not adjusting to them)
Skipping rest days
Only starting training now, so close to the event
The theme? Too much, too soon.
The “10% Rule” vs. The Long Run Effect
For years, runners have been told to follow the “10% rule”: don’t increase weekly mileage by more than 10%. But here’s the twist — new research shows the real culprit behind most running injuries isn’t total weekly distance, but your longest single run.
What the Research Found
A landmark study by Frandsen et al. (2025) followed over 5,200 runners for 18 months, looking at how spikes in training volume were linked to overuse injuries.
The researchers compared:
Weekly mileage changes
The longest single run compared to the runner’s previous 30 days
Results:
Small spikes (10–30% longer than your recent longest run) → 64% higher injury risk
Moderate spikes (30–100% longer) → 52% higher risk
Large spikes (>2x longest run) → 128% higher risk
Bottom line: It’s not weekly totals that matter most, but how far you go in your longest run.
What This Means for You
Think session by session, not just week by week.
Use the “30-day longest run” rule: Don’t increase any one run by more than 10% of your longest run in the past month (funny how the old 10% rule still sneaks back in).
Watch the “hero run”: That big Sunday long run is often where injuries creep in.
Return from injury carefully: Gradually progress your longest run, not just total weekly mileage.
Consistency beats heroics. Avoid over-ambitious single sessions and you’ll reduce your risk of injury — giving yourself the best chance to run stronger, longer, and pain-free.
Early Intervention Helps
Got a niggle in your calf, knee, or Achilles? Don’t wait until it stops you running. Our physios specialise in running injuries and can help you train safely through the final weeks.
✅ Book a Running Assessment – we’ll help you stay strong and race-ready
Want More Running Tips?
Check out our previous blogs to help you train smarter and avoid injuries:
Smart, gradual progression is your best defence against injuries. Focus on your longest runs, train consistently, get support when needed, and you’ll be ready to go (all going well…Kia Kaha!).
— Urban Athlete Physio Team
