Big Data gives marathoners new insights
A couple of days ago I looked at a training app from AI Endurance which closely looks at your individual performances and works out exactly what caused the good and bad adaptations in the past. The theory is that, in the future, you can improve your training by tailoring what you do more around workouts that have historically proved to be effective for you.
Another way of discovering what is effective is to look at much larger, population-wide data sets. The theory here is that you find a large group of similar, mid-pack runners (or whichever pack you are in) and then mimic aspects of their training or the aspects of training from similar athletes to you but who beat you 😉 . This is the BIG DATA approach.
Here’s a full article about this at triathlete.com which I found ‘obvious’ and ‘interesting’, both at the same time. Obvious that it tells us many things we already knew but interesting that it quantifies some of our beliefs with a dose of pesky science and offers up an odd mini-insight or two.
These were the key take-outs for MARATHON training which you could assume apply in principle to long-distance triathlons too:
Thorsten Emig looked at data from lots of athletes who have logged their data on Polar Flow. He found 4 things. I’ll mention these 3.
- Run More – and you can only run significantly more if you run slowly.
- Run faster for short distances and mitigate injury risks
- There is a point above which more training can be detrimental. This is 27,000 TRIMPs for the 6-months-to-date. (Google: TRIMP, even Strava’s relative effort uses it)
Then Barry Smyth (University of Dublin) looked at some big data from Strava. He found that a 4-week cycle seemed to be most effective. The themes of each week followed the Hard, Hard, Easy, Moderate pattern.
Easy means 2/3rd or even half the volume of other weeks and Hard means that 5k pace or Tempo pace work is included at least once. And remember this is for MARATHON training. So this broad approach seemed better than progressively and slavishly aiming to raise your weekly mileage and intensity.
Original Article: triathlete.com
Last Updated on 24 January 2026 by the5krunner
My favourite kit and nutrition
- Injinji – Runners protect your toes. Avoid discomfort and minor injury. Run more. Run faster. I use them.
- Garmin 90-degree charging adapter — The small adapter that keeps your charging cables tidy. Essential for race day. I use one.
- Garmin charging puck — the fastest and most reliable way to top up your Garmin before a session. I use one.
- Ravemen FR300 — Front light that mounts directly under your Garmin or Wahoo head unit. Keeps your bars clean and your beam pointed where it matters. I use one.
- Body Glide – The blue anti-chafe stick that all swimmers and many runners use. I use it.
- Maurten — The race nutrition trusted by elite athletes. Gels and drink mixes engineered to be easy on the stomach. I use them.
- Garmin Varia RTL515 — A radar rear light that alerts you to vehicles approaching from behind. Pairs with your Edge or Garmin watch. I use this model.
- Favero Assioma Pro RS2 — The power-meter pedals most serious cyclists choose. Accurate, easy to move between bikes. I use this model.
- Garmin Forerunner 970 — A serious choice for a pro-grade triathlon watch. I use this.
- Polar H10 — My daily driver for accurate, waking HRV readings.
- Wahoo ELEMNT Roam 3 — The bike computer that has the feature Garmin lacks: usability. I use mine on most rides.
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tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors. ID
How on earth do you look at your cumulative TRIMP? Flow can display Cardio load build up for the past 6months but it only lists TRIMP on individual activities.
In the training report bar graph you can see TRIMP by month in Polar Flow. I’ve already hit 28,000 for the year so I can now stop training.
😉
from memory it was 27k trimp for a rolling 6-month period, so you probably need to put your trainers back on and get out there