Polarized training is a way of organizing a training plan in which the majority of training stress occurs at low or high intensity. Unlike other approaches to training, in a Polarized training plan, little if any time is spent at moderate intensity.

Special thanks to TrainerRoad’s Amber Pierce for assistance in developing this blog post. For more on Polarized Training, check out Ask A Cycling Coach Ep 299.

Polarized training is a hot topic of conversation in modern cycling, given emerging research with promising results. Many studies suggest it can be an effective way to train in certain situations, but cycling-specific research on Polarized training remains relatively scarce and leaves many open questions. There is also widespread confusion and uncertainty about how to define Polarized training and how to compare it to other approaches, both in common conversations and in scientific literature. 

What is Polarized Training?

Polarized training is one specific type of training intensity distribution, a way of organizing and distributing intensity within a training plan (in cycling or in other sports).

Good training plans productively balance training stress with recovery over time, using a technique called periodization. Plans can be periodized in different ways, dividing the overall structure of stress and recovery into annual, monthly, weekly, or block-by-block cycles, for instance. Training intensity distributions such as Polarized training are a way of organizing training stress within a periodized structure.

Common Training Intensity Distributions

  1. High Volume Low Intensity Training (Long slow distance): Training composed mostly of long, low-intensity workouts; often associated with base training. 
  2. Threshold Training (THR): Training primarily occurring at moderate intensities, not to be confused with the Threshold Power Zone or Threshold intervals (these are actually high-intensity efforts)
  3. High Intensity Interval Training (HIIT): Training mostly composed of short, hard efforts at high intensity and low volume
  4. Pyramidal Training (PYR): Training at a mix of intensities, with the most time spent at low intensity, less time at moderate intensities, and the least time spent at high intensity. Most TrainerRoad training plans are Pyramidal in design.
  5. Polarized Training (POL): Training mostly at high or low intensity, with little to no time spent training at moderate intensity. 

Polarized training intensity distributions are most commonly defined in research as 80% low intensity and 20% high intensity, but this differs from study to study and is further complicated by how training time is measured. Some researchers define overall intensity for each training day (or for individual training sessions) and use the proportion of low-intensity to high-intensity days or sessions to define the distribution of intensity. Other researchers measure the actual time spent at a specific intensity during each workout, referred to as time-in-zone, and quantify intensity distribution this way. These two methods can arrive at very different definitions of what constitutes Polarized training, as a workout considered “high intensity” may actually include only a few minutes of actual high-intensity effort.

Inconsistencies in measurement and definition aside, Polarized training is quite distinct from other training intensity distributions. In a Polarized training plan, most workouts are low intensity, a few workouts are very hard, and almost none fall in-between. Polarized Training was first introduced as a concept by Dr. Stephen Seiler, based on his observations of training habits among elite rowers.

Defining Intensity

Since Polarized training is a way of distributing intensity in a training plan, it’s crucial to understand how intensity is actually defined. Pace, heart rate, perceived exertion, and power are all ways to measure the intensity of training stress. In cycling, researchers mostly use training zones based on power output. Within TrainerRoad, we use a cycling-specific 7-zone system defined as a percentage of FTP. Most research into Polarized training (and the rest of this blog post) uses a simpler 3-zone model applicable across endurance sports and measured in relation to VO2 max and Lactate Threshold.

The 3-Zone Intensity Model

  1. Zone 1 (low intensity) in the 3-zone model ranges from 50% of an athlete’s VO2 max to Lactate Threshold 1 (LT1), the point at which blood lactate levels begin to increase. Zone 1 in the 3-zone model mostly equates to the Endurance power zone in TrainerRoad. (Active Recovery riding below 50% of VO2 max is not considered part of Zone 1.)
  2. Zone 2 (moderate) ranges from Lactate Threshold 1 (LT1) to Lactate Threshold 2 (LT2), the point at which blood lactate levels begin to rise dramatically. LT2 is sometimes defined as a blood lactate concentration of 4.0 mmol/L, but this can vary widely from athlete-to-athlete. In TrainerRoad, this zone roughly correlates to Tempo and Sweet Spot training .
  3. Zone 3 (high-intensity) encompasses any time spent above LT2. In practice, this includes most riding above FTP, which in TrainerRoad encompasses most of the Threshold and VO2 Max power zones.

In an attempt to simplify the 3-zone model for athletes who don’t have access to blood-lactate testing, some researchers use ventilatory thresholds instead of lactate thresholds to define zones. Ventilatory thresholds VT1 and VT2 correspond reasonably well (but not perfectly) with lactate thresholds LT1 and LT2, respectively. Dr. Stephen Seiler has also defined the 3 zones by percentage of FTP for cyclists, with Zone 1 ranging from 50%-79% of FTP, Zone 2 80% – 99%, and Zone 3 at 100% or above. But even in the research literature, definitions for each zone can vary, and it’s important to keep in mind that how lactate or ventilatory thresholds correlate with percentages of VO2max power or FTP will vary from individual to individual. 

Polarizing Semantics

Adding one more point of confusion to the dialogue surrounding Polarized Training, the verb polarize is commonly used by cyclists to imply a shift in emphasis away from moderate intensity, towards more high- and low-intensity training. Athletes often discuss “polarizing” their training, but this usage can be irrespective of the definitions of Polarized training as a formal training intensity distribution. 

In any discussion about Polarized training, it’s important to know whether the conversation is referring to a casual reduction in moderate-intensity training – “polarization” – or whether it refers to a more intentional and systematic training intensity distribution – Polarized training. All mentions of Polarized training in this article refer to the formal, scientific definition.

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Research on Polarized Training 

Polarized training is a growing area of research in endurance sports. Many studies have found that it can result in certain performance improvements equal to or greater than some other training intensity distributions, especially over the short term. Other studies suggest Pyramidal training is equal or superior to Polarized for improving certain performance metrics. 

Currently, research on Polarized training spans a range of endurance sports, with commonly cited studies focused on skiers, runners, or rowers. Cycling-specific studies are relatively few, emerging more recently in the literature. So far, the narrowly-controlled protocols, limited timeframes, and small sample sizes in these studies make it difficult to draw conclusions about real-life applications for cycling.

Though limited when it comes to cycling, the evidence does suggest Polarized training can be effective, but it’s not clear whether it is best for all athletes in all circumstances. For example, studies suggest that Polarized training may impact athletes differently depending on training status. In other words, whether the athlete is relatively new to training or is already highly trained may make a difference. The research is also unclear on whether a Polarized training intensity distribution applied over the whole course of a training plan would be more or less effective than combining blocks of Polarized training with blocks of other training intensity distributions. 

“Polarized Training Intensity Distribution has been proven to be an effective strategy for some elite athletes during certain phases of the season,” concluded a 2015 review of available literature. But after acknowledging the limitations of the existing research, the review’s authors stopped short of declaring polarized training the best option, stating “consequently, an ‘optimal’ Training Intensity Distribution cannot be identified, and further prospective randomized investigations conducted over extended time-periods will have to be designed to address this question.”

If you want to check out the current research for yourself, we’ve linked to a number of studies at the bottom of this post.


While the jury is still out on whether one training intensity distribution is always better than another, a strong body of evidence in both scientific literature and in real-life application suggests a mixed approach to training can be highly effective. This is why periodization is so important to the success of a training plan – by strategically varying your training intensity distribution throughout the season, you can increase your odds of successfully reaching your goals. 

To use an example familiar to TrainerRoad athletes, linear periodization emphasizes lower intensity with higher volume early on, and shifts towards more high intensity and significantly less volume as target events grow near. In this approach, you front-load your season with training aimed at increasing your fitness, then eventually shift focus to reducing fatigue and maintaining specific fitness for your goal event. To be as effective as possible, training intensity distribution approaches like Polarized training still need to consider the bigger-picture periodization of a training plan over the course of a season, a year, or perhaps even longer timeframes.

Who is Polarized Training For?

Polarized training is a good option for athletes who want to experiment with an alternative way of distributing intensity in their training plan. While the scientific literature isn’t crystal clear on the specific athletes for whom Polarized would work best, there is strong evidence to support consistency and motivation as major factors for training success. In the end, the best training plan is the one that will best help you stay consistent and motivated, so if you are excited to try Polarized training, it may be a good option for you.

der plan with a new Polarized block. 

Example Polarized Cycling Training Plan

The high-volume 8-week Polarized Plan incorporates two 3-week loading cycles, each followed by a recovery week. Its total training intensity distribution is 92% Zone 1, 1% Zone 2, and 6% Zone 3 when measured by time-in-zone. Overall it averages about 9h training time per week, with a weekly maximum of 11.5h. 

The plan’s 5th week serves as a good example of its overall structure. The previous week is focused on recovery, so this week begins the plan’s second load cycle.

Week 5 of TrainerRoad’s high-volume Experimental 8-week Polarized Plan

By default, Monday is an off day. Tuesday features an intense VO2 max workout, with nine 2-minute intervals at 122% FTP and 3-minute recoveries. Wednesday and Thursday are endurance workouts, and a very challenging Threshold workout on Friday includes four 16-minute intervals at 100% FTP. Finally, the weekend is occupied by low-intensity endurance workouts. Saturday’s ride is only 1 hour to allow for recovery from Friday’s efforts, but Sunday’s workout is a longer 3-hour endurance ride. Sunday workouts increase in length (but not intensity) over the course of the plan, eventually reaching 5 hours during week 7.

Mid- and low-volume versions of the plan are similar but include fewer overall training days and correspondingly less intensity, in order to maintain an 80/20 intensity distribution. The mid-volume plan includes 4 total workouts each week, while the low-volume version is based on 3 workouts per week.

Week 5 of TrainerRoad’s low-volume Experimental 8-week Polarized Plan

Polarized Training References and Further Reading

Hydren, J. R., & Cohen, B. S. (2015). Current Scientific Evidence for a Polarized Cardiovascular Endurance Training Model. Journal of Strength and Conditioning Research, 29(12), 3523–3530. doi:10.1519/jsc.0000000000001197

Kenneally, M., Casado, A., & Santos-Concejero, J. (2017). The Effect of Periodisation and Training Intensity Distribution on Middle- and Long-Distance Running Performance: A Systematic Review. International Journal of Sports Physiology and Performance, 1–26. doi:10.1123/ijspp.2017-0327 

Laursen, P. B. (2010). Training for intense exercise performance: high-intensity or high-volume training? Scandinavian Journal of Medicine & Science in Sports, 20, 1–10. doi:10.1111/j.1600-0838.2010.01184.x 

Muñoz, I., Cejuela, R., Seiler, S., Larumbe, E., Esteve, J. (2013). Training-Intensity Distribution During an Ironman Season: Relationship With Competition Performance. International journal of sports physiology and performance. 9(2), 332-339. doi:10.1123/IJSPP.2012-0352.

Muñoz, I., Seiler, S., Bautista, J., España, J. (2013). Does Polarized Training Improve Performance in Recreational Runners? International journal of sports physiology and performance. 9(2), 265-272. doi:10.1123/IJSPP.2012-0350.

Neal, C. M., Hunter, A. M., Brennan, L., O’Sullivan, A., Hamilton, D. L., DeVito, G., & Galloway, S. D. (2013). Six weeks of a polarized training-intensity distribution leads to greater physiological and performance Adaptations than a threshold model in trained cyclists. Journal of Applied Physiology, 114(4), 461-471. doi:10.1152/japplphysiol.00652.201

Pérez, Sergio & Fernández-Sáez, José & Cejuela, Roberto. (2019). Pyramidal Training Intensity Distribution: Relationship with a Half-Ironman Distance Triathlon Competition. Journal of sports science & medicine. 18. 708-715.

Rønnestad, B. R., Hansen, J., Nygaard, H., & Lundby, C. (2020). Superior performance improvements in elite cyclists following short intervals vs. effort‐matched long intervals training. Scandinavian Journal of Medicine & Science in Sports. doi:10.1111/sms.13627 

Rosenblat, M. A., Perrotta, A. S., & Vicenzino, B. (2018). Polarized vs. Threshold Training Intensity Distribution on Endurance Sport Performance. Journal of Strength and Conditioning Research, 1. doi:10.1519/jsc.0000000000002618 

Seiler, S. (2010). What is Best Practice for Training Intensity and Duration Distribution in Endurance Athletes? International Journal of Sports Physiology and Performance, 5(3), 276–291. doi:10.1123/ijspp.5.3.276 

Seiler, S., Haugen, O., & Kuffel, E. (2007). Autonomic Recovery after Exercise in Trained Athletes. Medicine & Science in Sports & Exercise, 39(8), 1366–1373. doi:10.1249/mss.0b013e318060f17d  

Stöggl, T., & Sperlich, B. (2014). Polarized training has greater impact on key endurance variables than threshold, high intensity, or high volume training. Frontiers in Physiology, 5. doi:10.3389/fphys.2014.00033 

Stöggl, T. L., & Sperlich, B. (2015). The training intensity distribution among well-trained and elite endurance athletes. Frontiers in Physiology, 6. doi:10.3389/fphys.2015.00295 

Treff, G., Winkert, K., Sareban, M., Steinacker, J. M., Becker, M., & Sperlich, B. (2017). Eleven-Week Preparation Involving Polarized Intensity Distribution Is Not Superior to Pyramidal Distribution in National Elite Rowers. Frontiers in Physiology, 8. doi:10.3389/fphys.2017.00515