THE SHORT ANSWER
Here's what most amateurs get wrong about polarised training: it isn't a trend, it's what Seiler measured. When he studied elite cyclists, rowers, runners and cross-country skiers — groups who weren't talking to each other — they'd all landed on the same split. Roughly 80% of the work genuinely easy, 20% genuinely hard, almost nothing in the middle. On the podcast he's blunt about why that middle ground costs you: the grey zone feels like training, but it mostly just burns matches. It accumulates fatigue faster than it drives adaptation. The fix isn't more suffering. It's the discipline to ride your easy days easy enough that your hard days actually count. That's the whole thing. Get the distribution right and the gains look after themselves.
WHO IS STEPHEN SEILER?
Stephen Seiler is the exercise physiologist who, more than any other researcher, defined how modern endurance athletes structure their training. Working from his lab at the University of Agder, he documented that elite athletes across cycling, rowing, cross-country skiing and running converge on the same intensity distribution — roughly 80% easy, 20% hard, with very little time in the middle. That observation is now known as polarised training and the 80/20 rule, and it is the framework Roadman builds every training conversation on.
SEILER ON POLARISED TRAINING
Seiler’s key positions on polarised training.
- Polarised training: ~80% of sessions at low intensity, ~20% at high intensity, very little time in the threshold/tempo grey zone.
- Elite endurance athletes across disciplines converge on the same intensity distribution — it is not a coaching opinion but a measured pattern.
- The biggest single mistake amateurs make is riding their easy days too hard, which compromises the quality of their hard days.
IN SEILER’S OWN WORDS
Verbatim from Stephen Seiler’s appearances on the podcast.
“what we've seen that across Sports we've collected data from some of the best performers in the world in running in CrossCountry skiing in cycling and Rowing and so there's a bit of a universality to this that they're roughly doing about eight out of 10 sessions training sessions are essentially low stress days they're doing lots of work but they're keeping the lactate low they're in that green zone and then two to three days a week or sessions out of 10 are the more high stress”
“I do not know of data that has been published and subjected to peer review that shows that doing recovery rides accelerates recovery compared to sitting on the sofa. if you're really tired I say take a rest day meaning an actual rest day where you don't ride people are scared to death of that but they shouldn't be”
“the really good endurance athletes they may be cruising along at .7 Millar lactate whereas the average person is at 1.8 you know so they are really able to work with very low you know low turnover of lactate and so that may be you may be saving them glycogen basically”
“What I saw is that athlete populations from diverse sports that really weren't talking to each other or independent of each other finding the same solution to a problem to a biological challenge.”
HEAR IT ON THE PODCAST
Episodes where Stephen Seiler covers polarised training and related ground.
FREQUENTLY ASKED
What does Stephen Seiler say about polarised training?
Here's what most amateurs get wrong about polarised training: it isn't a trend, it's what Seiler measured. When he studied elite cyclists, rowers, runners and cross-country skiers — groups who weren't talking to each other — they'd all landed on the same split. Roughly 80% of the work genuinely easy, 20% genuinely hard, almost nothing in the middle. On the podcast he's blunt about why that middle ground costs you: the grey zone feels like training, but it mostly just burns matches. It accumulates fatigue faster than it drives adaptation. The fix isn't more suffering. It's the discipline to ride your easy days easy enough that your hard days actually count. That's the whole thing. Get the distribution right and the gains look after themselves.
What is Seiler's main point on polarised training?
Polarised training: ~80% of sessions at low intensity, ~20% at high intensity, very little time in the threshold/tempo grey zone.
Which Roadman Cycling Podcast episodes cover Stephen Seiler on polarised training?
Seiler discusses polarised training in these episodes: "Secret To Cycling Fast At A Low Heart Rate | Prof Seiler", "80/20 Training to Ride Faster | Dr Stephen Seiler".
MORE FROM SEILER
EXPLORE THE TOPIC
Training Plans— The Complete Guide →OTHER EXPERTS ON POLARISED TRAINING