Podcast, Science, Training

Polarised training Q&A and Mikael’s perspectives part 2 | EP#185

 June 10, 2019

By  Mikael Eriksson

​​Polarised training Q&A and Mikael's perspectives part 2 | EP#185

TTS185 - Polarised training Q&A and Mikael's perspectives part 2

An in-depth discussion and Q&A session on the ins and outs and dos and don'ts of polarised training for triathletes and endurance athletes in general. This episode is part 2 of a Q&A follow-up to the extremely popular interview with the godfather of polarised training, Dr. Stephen Seiler in EP#177.

Discuss this episode!

  • Let's discuss this episode and the topic in general. Post any comments or questions in the comments at the bottom of the shownotes. Join the discussion here!

In this Episode you'll learn about:

  • How can polarised training apply to age-group triathletes?
  • Polarised training for beginner athletes, masters athletes, and for longevity and health (rather than performance).
  • Periodisation with polarised training.
  • Differences in applying polarised training between disciplines, distances and events. 
  • The physiology of polarised training. 

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Time crunched age groupers

4:05 -

Q (from Patrick): If you're a cyclist and you're training for 7-8 hours per week, you probably can't do 4-5 hour rides. Is a schedule with 2 high intensity sessions, and the remaining 90-100 minutes at low intensity going to be a benefit? Or would sweet spot/threshold/VO2max mix be a better option?

  • It's not either or, you do have high or moderate intensity, but you need the low intensity foundation. 
  • High volume at low intensity is what you are aiming for - the vast majority of training is low intensity, even at 7-8 hours. 
  • You will still be doing VO2max/sweet spot/threshold depending on where you are in training, and your goals still, but a lot of work would be low intensity. 

Q (from Martin): Is 90/10 (total duration) polarised split relevant for an amateur athlete training 6-10 hours per week, when the low intensity sessions are unlikely to be long enough to make adaptations the same as the long zone 2 rides if you did 16 hours per week?

  • The rides don't have to be 4 hours long to create adaptations, it's more about consistency over time.
  • It's great to get in a weekly long ride, and ideally have 2 per month that are around 4 hours long, but short workouts are still of great value. 
  • Hypothetically if you have 2 twins, and one was sedentary while one went for a 20 minute run every other day. 

    Those 20 minute runs are going to make a massive difference. 
  • 20 minutes is better than nothing. 

Q (from Anthony): What Seiler's viewpoint on the real world applicability of polarised training for those that have a maximum of 8-10 hours to train per week and can't always budget time for 4+ hour ride each week?

  • See Episode 178 for the case study about Stephen Seiler himself, who trains on a time crunched schedule. 
  • You don't have to go for 4 hours every week, 2 hours would be plenty - or possibly you could do 2 x 2 hours (one on Saturday and one on Sunday). 


10:19 -

Q (Saba): What does periodisation look like with polarised training, is it always an 80/20 split between low and high intensity, or does it range from 90/10 - 40/60 depending on the phase you are in?

  • It can fluctuate a little but not too much - in particular the distribution of the low intensity training should not change much.

    Stephen mentioned that in cross country skier their training becomes even more polarised closer to the race, but in triathlon I think he means the easy workouts just become easier and the harder workouts become harder. 
  • I agree, do the easy work even easier closer to a race, and the hard work harder but I think it also becomes more race specific. 

    E.g. for a long distance triathlete it actually becomes less polarised because you go from more high intensity training to moderate intensity to suit the race. 

    However the duration may increase, doing long race pace efforts.

Q (from DarthShivious): For amateur cyclists many ride 8-12 hours per week and this time is precious, while seeking a goal to peak across a season of races. Would you suggest an 80/20 split both pre-season and during the season? If yes, what key workouts would you suggest these athletes program? 

E.g. Tuesday 4x8 minutes @ 105% FTP, Thursday 2x20 minutes @ 95% FTP, Saturday long ride 3-4 hours

  • Regarding the split pre- and during the season, yes, the split should ideally remain the same. 
  • Regarding the workouts, those would be three great workouts depending on your event.

    If you're a criterion racer it may look very different, but for triathletes and time trialists that would be great. 
  • You will also need a couple of shorter, easier workouts in there too.

    Ideally 1-1.5 hour easy rides, depending on how much time you have. 

Q (from Chester): Is the polarised approach applicable after the base phase and what are the minimum number of hours required to get a benefit from the polarised approach? 

  • It is a year round plan, and the term depends on the sport you are doing. 

    E.g. if you're a long distance athlete you do the same amount of low intensity training but how you use your non-low intensity training may be different from a rower or a skier.

    You will do more moderate compare to high intensity training. It may be an 80/15/5 split compared to an 80/5/15 split. 
  • For me personally, my training becomes more specific closer to the race which means more moderate intensity training. 

    This would be for more triathlon distances, including sprint, which is generally raced at threshold but not above. 
  • Regarding the minimum number of hours, the results may not be as quick as on a high intensity programme if you have a low amount of weekly hours. 

    However, they will likely sustain for a longer period of time so you will likely develop better long term. 

    They will also set you up to absorb more training later on - if you increase this volume later you will adapt better. 

    Even if you increase your intensity later on and move away from a polarised approach, you will probably still absorb it slightly better.
  • Stephen discusses this and the term biological durability. I tend to use the term fatigue resistance, which Joel Filliol uses a lot too.

    Either way, this is what you build using low intensity training, and it allows you to absorb more training and absorb it better. 
  • If you have a long term view you don't have to train a lot of hours for this concept to be a sensible way to structure your training. 
  • As for number of hours, studies have been done in 6-7 hours per week, but most in age-groupers still have some question marks around them. 

    Anecdotal evidence is also valuable here!

Q (from Nunu): Is traditional periodisation dead? If the adaptation to a consistent and prolonged stimulus will diminish with time, wouldn't it be a good idea to alternate polarised macro blocks with pyramidal macro blocks to keep varying that stimulus?

  • Lack of periodisation doesn't mean that training doesn't change.
  • Periodisation is the idea that we can use pre-defined structures of a combination of intensity, duration etc to create a predictable response to training. 

    This doesn't really work because so many variables go into this.

    For more information on this listed to Periodisation Theory: Confronting an Inconvenient Truth with John Kiely | EP#148.
  • I would agree that it makes sense to use blocks of different focuses, but the amount and type of low intensity training is unlikely to change. 

    You may start in pre-season with long low intensity rides, and build up to longer ones closer to the season, but the proportions would remain the same. 
  • What changes is what you do with the rest of your training, and the split between moderate and high intensity. 

    How you do this can be different depending on you as an individual, your strengths and weaknesses, goal event etc. 
  • Personally as a coach, I would not recommend training strictly polarised if all your low intensity is at or above threshold for the year. 

Differences between distances and disciplines 

21:58 -

Q (from Tim): In what ways should we approach training for running differently compared to cycling and swimming?

  • I have seen great success by doing more mid-zone work on the run compared to the bike and swim. 
  • The primary reasons are injury prevention and recovery - doing high intensity stuff when running is so much more demanding than on the bike or swim as much more muscle damage takes place.

    As a triathletes these helps too as you retain the quality of your subsequent sessions. 
  • It's usually much easier to recover from high intensity workouts when you're biking or swimming. 

Q (from Cary): Can you cover training for sprint distance triathletes where intensity may be more important?

  • It's still just as important for sprint distance to build the base of low intensity. 

    There will need to be just as much low intensity proportionally to your higher intensity work for this distance. 
  • What you do with the rest of your training will differ - for a sprint distance you have higher intensities and will be working a lot of threshold or slightly above. 

    You will therefore be doing more very polarised work, with your high intensity being very high compared to a long distance triathlete who may have more mid-zone work. 
  • Your easy long rides or runs - which aren't needed just to finish a sprint but will help optimise your performance - will still be at low intensity. 

    They don't have to be as long as a long distance athlete, but ideally still around 90 minutes run and 3 hour ride if you're really trying to optimise performance. 

    This would also be padded with plenty of low intensity sessions where you can work on technique etc. 

Polarised training and VLAmax (lactate building rate)

25:55 - 

Q (from Thomas): Dr Seiler's views on the concept of increasing VO2max and decreasing VLAmax as presented in the interview with Sebastian Weber, especially as the purpose of decreasing VLAmax which contradicts the original purpose of polarised training?

  • From discussing this with Stephen we concluded that it does not contradict it. It may have done when the polarised was periodised strictly, but it has now become more high low intensity training. 

    If you consider it from that perspective it doesn't contradict it. 
  • If you do an ISCYD test and you find you have a high VLAmax and want to decrease it to improve your threshold, it doesn't mean you start to do 50% of your training at moderate intensity. 

    It means that what you allocate you non-low intensity training time to may be sweet spot or threshold or tempo, as these work to decrease VLAmax. 
  • Physiologically, every athlete wants to increase their VO2max. 

    The number one way to consistently and sustainably increase your VO2max is to have a consistent volume of low intensity training. 
  • Remember that pyramidal does not mean 50/40/10 (low/mod/high), it means something like 80/15/5 or 80/20/0.

    When we talk about decreasing VLAmax needing a more pyramidal approach, it still falls under the polarised training umbrella. 

Q (from Dave): Does the effectiveness of the polarised model vary based on athlete profile. For example if an athlete has a high VLAmax will polarised training be effective and sufficient to raise FTP? Is a lack of sweet spot work in polarised training a flaw for an athlete trying to reduce VLAmax?

  • Anything you do to increase VO2max also improves threshold. 
  • For the second part, you would just allocate non-intensity training hours to the type of training that would reduce VLAmax. 

    That being said, truly polarised training in the strictest sense may not be ideal if you have a high VLAmax. 

General physiology and polarised training

32:05 - 

Q (from Bioteknik): Does power or pace at LT1 (aerobic threshold) compared to VO2max power pace move around much? Is the percentage of VO2max power at LT1 something that can be improved through training or is it more static within an individual and only increases in conjunction with increases in VO2max?

  • In my experience it can move a lot, even without changes in VO2max. 

    This is one of the main things we want to improve in endurance athletes in general, but particularly long distance athletes. 
  • This is another great argument for high low intensity training, as it's the main way you can move LT1 to a higher percentage of your VO2max, even without improving your VO2max itself. 
  • At a certain point you will get specific and do training right at LT1, e.g. one run with a segment of 60-90 minutes at LT1 heart rate/pace/power. 
  • In general, sticking to 80% of training at low intensity that will give you a lot of improvement in how high you can get your LT1 power or pace as a percentage of your VO2max power or pace. 

Q (from Martin): Stephen mentioned that when truly in your low-intensity zone there should be minimal heart rate drift. Can this idea be used to find the first lactate turn point (LT1)? For example with running, could you increase the speed of your low intensity runs to gradually find the point at which your heart rate begins to drift, and therefore where your LT1 is? 

E.g. Week 1, 9 minutes/mile, minimal heart rate drift
Week 2, 8:55/mile, minimal HR drift
Week 3: 8:50/mile, minimal HR drift
Week 4: 8:45/mile, significant HR drift.
Week 5 & beyond, zone 1 runs return to slower than 8:45/mile with HR drift in check.

  • This is an interesting concept but I wouldn't trust the accuracy of this test as there are too many factors that influence heart rate drift. 

    Even if you control for most of them, I don't think it will necessarily start drifting as soon as you cross the first lactate threshold so it wouldn't be accurate or precise. 
  • It could potentially give you a rough benchmark but not anything with confidence. 

Other questions

36:44 - 

Q (from Hainsworth): Has Stephen Seiler killed off the need for professional coaches prescribing overly complicated training sessions to make their clients feel they are getting value, when really you just need to train easy for a very long time and hard for a very short time?

  • This is funny because training easy for a long time and hard for a short time is definitely easier said than done! 
  • All athletes including in the research on polarised training on the elite side are World Class athletes and all have coaches - this tells you something! 
  • The role of the coach has never been to prescribe overly complicated training sessions, it's just as much about telling athletes what they're doing right or wrong in executing the training plan. 

Q (from Lee): In order to achieve long sessions at low intensity, I think it would be easier indoors (treadmill for run, smart trainer for bike). Is there any drawbacks to spending a large part of training indoors?

  • No, there's no drawback but you don't want to completely eliminate outdoor training. 

    You still want some specificity in training.
  • On the bike it's really helpful to learn to use terrain to your advantage and use momentum etc. 

    Also on the run, learning to run any kind of hills effectively and run at the right pace on this terrain. 
  • Dealing with weather conditions is also important, which you don't get indoors. 
  • With running in particular, you need to get muscle resistance to deal with the pounding on the streets as opposed to the treadmill which is a different feeling. 

Q (from Rickar): What are the consequences if you unintentionally cross the first lactate threshold ceiling for low intensity for a few minutes (e.g. when running or riding up a hill)? Is it more important to think about the average heart rate compared to time in zone heart rate?

  • It's not a problem if there are shorter periods above that threshold.
  • The important thing is time in zone, not average heart rate. 

    E.g. 10% of your run or ride might end up higher than threshold, which isn't a problem. 

    However, if 50% of your time is spent above threshold that's an issue, regardless of whether your average heart rate is in that zone or not. 

Q (from Rickar): What should you do regarding warm ups with easy training compared to high intensity training?

  • There's no specific warm up needed, I would recommend going off by feel and making sure you go easy enough. 
  • For me, the first 10 minutes are usually the slowest while I'm still getting warmed up, it's at the same easy effort and heart rate increase until it settles in low intensity zone.
  • For swimming and running it's great to do a short mobility routine for the warm up, but this is more for technique rather than physiological or cardiovascular reasons. 

Q (from Rickar): I base my running and riding zones from the ones you prescribed in an earlier episode, but you calculate the threshold heart rate in a 20 minute test and work out all zones from there. However, are you now transitioning to using max heart rate? How do you calculate zones here?

  • The way I use zones now has indeed evolved a bit so the earlier episodes aren't the same. 
  • I prefer to prescribe and execute low intensity sessions based on heart rate, and RPE.

    Heart rate and RPE should both be low during easy workouts. 

    If heart rate is low but RPE is moderate or high, you should still slow down!
  • In terms of heart rate I have two options for calculating zones - I use both and see which fits best. 
  • The first is based on a 20 minute test or a max 20 minute heart rate. 

    This may be a climb on a training ride or a race situation. 

    If you use the 20 minute method, I calculate the lactate threshold heart rate (LT2 heart rate) as 94% of that 20 minute max heart rate. 

    For the ceiling for low intensity training zone (LT1), this is 86% of threshold heart rate. 
  • For example, you do a 20 minute test and your heart rate is 180.

    - 94% of max heart rate would be 169bpm (lactate threshold heart rate)
    - 86% of threshold heart rate would be 145bpm (ceiling for low intensity training)
  • If you don't need your lactate threshold heart rate, you can take .81x180 which would give your 86% also. 
  • With heart rate max I go straight to calculating LT1.

    I use the 75% proposed by Stephen Seiler. 
  • Generally when I have good data from an athlete these two tests will give very similar results.
  • For the example above, is they did 180 average for the 20 minute test and have a max heart rate of 193, it would give the same 145bpm as threshold. 
  • If there is a difference I tend to go with the option that gives a higher approximation for LT1. 

    It tends to be the 20 minute heart rate approach. 
  • For moderate intensity training and high intensity training I prefer pace, power and RPE as primary metrics for intensity. 
  • When using that on a 20 minute test as a basis, I use 91% of pace/power, not 95% to get to threshold pace or power.
  • After this I take the threshold and for cycling using the Coggan zones:

    55% = Zone 1
    75% = Zone 2 (low intensity ceiling)
    90% = Zone 3
    105% = Zone 4
    120% = Zone 5.
  • For running pace and power I use my own zones that I've found work well through trial and error. They are:

    74% of threshold = Zone 1 ceiling
    85% = Zone 2 ceiling
    95% = Zone 3 ceiling
    103% = Zone 4 ceiling
    112% = Zone 5 ceiling.

    The main difference is that the ceiling of zone 2 ends up being lower than most other systems. 
  • I have a spreadsheet where you can use all of these methods to calculate your zones. 

Q (from Matteo): Regarding zone 4 training, Seiler seems to indicate that zone 4 starts at the second threshold. Comparing this to the 5 zone model used in cycling, zone 4 normal starts at 90% of FTP. If we have a properly estimated FTP, would Seiler's zone 4 actually start right at that threshold?

  • It's tricky to compare as the 5 zone model Seiler references is the one used by the Norwegian Olympic Committee. 

    It's based on lactate and/or percent of max heart rate. 
  • Zone 4 in that system is 4-6mmol of lactate. 

    This means on average it would start right at your threshold as most people's second threshold is here. 
  • If you look at heart rate or percent of max heart rate we see that that zone stretches from 87-92% of max heart rate. 

    This is harder to interpret and Dr Seiler said typically lactate threshold heart rate ends up being around 90% of max heart rate. 
  • In that model you can see that zone 4 doesn't start as low as 90% of FTP but it may start a bit below threshold when using the heart rate approach - maybe 95%. 
  • Since your threshold is a moving target, try not to see it as a point but rather a range. 
  • The zone 4 is set a little higher in the 5 zone model than traditional Coggan models. 

Q (from Colin): If you go down the lab based lactate testing route, how frequently would you need to re-test? I assume it's similar to FTP which is hopefully increasing, does your LT1 also move around? Will the tests be done on both running and cycling, or just cycling and then scale it?

  • Hopefully LT1 also does shift significantly. 
  • A common consequence of not doing enough low intensity training, or not doing the low intensity easy enough is that LT1 doesn't shift - we're trying to avoid this. 
  • In an ideal world you'd be testing at least 4 times per year, ideally both cycling and running. 
  • The great thing is that if you use heart rate, these zones will not change much if at all in a season. 
  • Therefore, you can test one and then use heart rate and RPE to see you through the season. 

    You would use performances in races as benchmarks. 
  • You probably don't need to constantly know your LT2 power and pace if you're constantly improving anyway. 
  • As for cycling versus running, if you're really on a budget you can scale your heart rate zones from cycling to running or vice versa. 

    E.g. if you know your running max heart rate is 190, and your cycling max heart rate is 180, I would subtract 10 from all your bike heart rate zones based on a running test you performed. 
  • To give an example, I prefer doing low intensity training monitoring heart rate and RPE. 

    For moderate and high intensity training I prefer power, pac and RPE. 
  • Imagine you have a 3 x 15 minute threshold workout. 

    You know what threshold feels like from tests, and you know your heart rate (which can be a help in this session but don't let it govern it). 

    It becomes a question of going at the intensity you can just sustain for 15 minutes.
  • This goes for all workouts, if it's 4 x 4 minutes at VO2max go just about as hard as you can sustain for 4 x 4 minutes. 
  • You shouldn't absolutely kill yourself or PR in your workouts. 
  • If you rate yourself on a scale of 1-10, you want hard workouts to be 8-9/10 almost every single time, very rarely do you want a 10/10. 

    You want to be close to the limit but not quite at it. 
  • You should still measure power and can use it as a baseline. 

    If you know you did 3x12 minutes at 300 watts last week, and then this week felt good and you try to sustain 305 watts, use that knowledge. 

    However, if your threshold was 290 a few weeks ago, doing it at this exact power may hold you back. 

    This is why you don't necessarily need to know your LT2 throughout the whole season, and base your workouts one exact percentages of that. 

Links, resources and contact

Links and resources mentioned

    Connect with host Mikael Eriksson


    Hi! I'm your host Mikael,

    I am a full-time triathlon coach and an ambitious age-group triathlete. My goal is podium at the Finnish national championships within the next few years.

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    Mikael Eriksson

    I am a full-time triathlon coach, founder of Scientific Triathlon, and host of the top-rated podcast That Triathlon Show. I am from Finland but live in Lisbon, Portugal.

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