Norwegian double threshold training – what it is, how it works, and who it is for

Norwegian double threshold training, often referred to as double-threshold training, has in recent years become one of the most widely discussed concepts in endurance sport, largely due to the high-profile success of athletes such as Jakob Ingebrigtsen and other leading Norwegian runners. However, the model itself is not new; it was originally developed by runner and researcher Marius Bakken, who began refining a structured approach to threshold-based training.

The method is not simply a matter of “training hard twice a day”, but rather a highly precise, regulated physiological stimulus designed to maximise aerobic load without pushing the body into excessive metabolic stress. It relies on careful planning, strict control of intensity zones, and deliberately managed recovery. For this reason, it is not entirely suitable in its pure form for recreational athletes; however, certain elements of the approach can be effectively incorporated into most training programmes.

WHY DOES THIS WORK? THREE KEY PHYSIOLOGICAL MECHANISMS

In the double-threshold model, a single day includes two separate threshold workouts, typically spaced 6–8 hours apart. For example, a longer set of intervals may be performed in the morning and shorter intervals in the evening, with both sessions kept strictly below the lactate threshold. A typical target range is around 2–3 mmol/L, or at most approximately 3–4 mmol/L, depending on the workout. In practical terms, this corresponds to roughly 80–87% of maximum heart rate in well-trained runners (Bakken, 2026).

The key principle is this: the effort should not exceed the threshold, but rather remain “hovering” around it.

Many people interpret threshold training as “hard but controlled”, but in the Norwegian model, the control is taken to a much higher level. Training is often carried out using lactate measurement devices to ensure that intensity remains within the desired range. However, this does not mean that every single session is monitored with lactate testing, as there will always be variation between days and environmental conditions. That said, measurements are taken frequently enough to allow training intensity to be tracked using additional markers as well, such as heart rate, pace, and RPE (rate of perceived exertion).

WHY MIGHT TWO TRAINING SESSIONS PER DAY BE BETTER THAN ONE LONGER SESSION?

At this point, one of the more interesting findings from recent years comes into focus. Kjøsen Talsnes et al. (2024) compared a single prolonged interval session with two separate sessions, where the total training load was the same. The results were surprisingly clear. In the continuous long session, heart rate and lactate were observed to rise towards the end, alongside an increasing sense of perceived exertion. This is a classic “cardiac drift” phenomenon. In contrast, in the split-session format, physiological load actually decreased in the second session, and athletes reported better recovery, as well as less muscle soreness the following day (Kjøsen Talsnes et al., 2024).

From a practical perspective, this means the same total work can be completed with a lower overall strain. In other words, training quality remains higher, as the body is able to sustain work at a higher intensity for longer without excessive fatigue accumulating. However, this does not mean that all longer high-intensity sessions should be replaced with split workouts, nor that training should always be divided into two parts. Endurance athletes, and particularly marathon runners, also need to include longer sustained high-intensity sessions in order to adapt to working under fatigue. It is therefore more a question of periodisation and timing within the training cycle. As Kelemen et al. (2023) note, elite athletes shift their emphasis towards race-pace specificity as competition approaches.

DOUBLE THRESHOLD IN PRACTICE, AND WHO IT IS SUITABLE FOR

The aim is not to “go hard”, but to remain in a tightly controlled zone where the aerobic system is working at near-maximal capacity without allowing the anaerobic system to take over. This is often where athletes go wrong, by running too hard and turning what should be two controlled sessions into two very demanding workouts in a single day.

According to Kelemen et al. (2023), elite endurance runners typically perform around 75–80% of their total training volume at low intensity, with threshold work carried out 2–4 times per week. In practice, this can include double-threshold days approximately twice per week. This corresponds to very high weekly training volumes (around ±200 km per week) and is characteristic of elite-level athletes.

As such, the model is not primarily intended for most recreational runners, as it requires a highly developed aerobic base, strong recovery capacity, precise intensity control, and often the use of lactate measurement to ensure training is executed correctly.

NORWEGIAN SINGLE THRESHOLD TRAINING – A SENSIBLE ALTERNATIVE FOR RECREATIONAL RUNNERS

Most runners are likely to benefit more from a so-called Norwegian single-threshold model, in which threshold sessions are performed 2–3 times per week, rather than on consecutive days or twice within the same day. The objective remains the same as in the double-threshold model: to stay below the lactate threshold while sufficiently stressing the aerobic system. The intensity zone is identical or sub-threshold, with longer intervals typically performed close to marathon pace and shorter intervals closer to half-marathon pace.

The double-threshold approach requires an exceptionally high recovery capacity, which most working runners simply do not possess. In addition, monitoring equipment can be expensive, and overall training load can easily become excessive if not carefully controlled. It is also important to recognise that not all speed work should be threshold-based; overreliance on this type of training can, in some cases, actually blunt speed development. The method is often most effective during base-training phases or for runners who habitually train too hard.

Alongside threshold work, faster interval sessions and longer race-pace efforts are still necessary to develop overall capacity, fatigue resistance, and pacing control.

If you’re looking for a consistent training program that includes speed training and progresses progressively, check out the online store for running programs.

Resources:

Bakken, 2026, https://www.mariusbakken.com/double-threshold-training.html

Kelemen, B., Benczenleitner, O., & Tóth, L. (2023). The Norwegian double-threshold method in distance running: Systematic literature review. Scientific Journal of Sport and Performance, 3(1), 38–46. https://doi.org/10.55860/NBXV4075

Kjøsen Talsnes R, Torvik P-Ø, Skovereng K and Sandbakk Ø (2024) Comparison of acute physiological responses between one long and two short sessions of moderate-intensity training in endurance athletes. Front. Physiol. 15:1428536. doi: 10.3389/fphys.2024.1428536