The Norwegian method and double threshold: what is actually proven

What the Norwegian method is

The Norwegian method describes how a group of elite Norwegian runners trained. A summary by Casado, Foster, Bakken and Tjelta (2023), written partly by the method’s own architects, gives its core:

• High easy volume: 150–180 km a week.
• Three to four threshold sessions a week, guided by blood lactate at 2–4.5 mmol/L. Lactate is a by-product of burning carbohydrate. A threshold session is run just below the point where it starts to build up quickly.
• One VO2max session a week. VO2max is the most oxygen your body can use per minute. VO2max sessions are hard intervals of a few minutes.
• “Double threshold” days: two threshold sessions on the same day, several hours apart.

The long run in the elite template is short by marathon standards, about 21 km.

What its architects say

The same authors were frank about the evidence. In plain terms, they wrote that no controlled studies have tested how well the model works. They noted that it had been described only in 1500 m and 5000 m runners, so its value for the marathon is uncertain (Casado and colleagues, 2023).

That is the most important fact on this page. The method is built from training logs of very successful athletes, not from trials comparing it with other approaches.

The experimental evidence

The only experimental data on double threshold are short-term. In 14 trained men, two sessions of 3 × 10 minutes, 6.5 hours apart, caused less physiological strain than one session of 6 × 10 minutes (Kjøsen Talsnes and colleagues, 2024). That supports the idea behind splitting the work: you may be able to pile up more time at threshold for the same cost. It says nothing about whether you will race faster.

Interviews with Norwegian world-class coaches describe two to three key days a week holding three to five hard sessions in total (Sandbakk and colleagues, 2025). Again, this is a description of practice, not a test of it.

A 2026 comparison looked at East African training, which varies a lot from day to day, and Norwegian training, which packs in threshold work. It concluded that both produce world-class runners, so no single model is the best (Grivas, 2026).

Indirect support for a moderate version

Older trials give some indirect support for longer, controlled threshold-type intervals. In trained recreational cyclists, four 8-minute intervals at about 90% of maximum heart rate beat four 4-minute intervals at about 95% (Seiler and colleagues, 2013). That is a different sport and not a test of the Norwegian method, but it fits the idea that moderate-hard intervals can be effective.

“Norwegian singles”

An amateur version, often called “Norwegian singles”, uses two to three sub-threshold sessions a week on separate days instead of double days. It rests on single-runner forum reports and book claims, and those accounts don’t agree with each other on the details (Marathon Handbook summary). The mechanism is plausible, but the evidence is anecdote.

If you want to try it, here is our suggestion, not a finding: two sessions a week, never on back-to-back days, with 25–45 minutes of work split into short reps with short rests. Without a lactate meter, run them at an effort where you can still speak in short phrases. Count these runs as zone 2, the steady zone between the two thresholds.

Double days are a bigger step. As a cautious suggestion, save them for runners with years of consistent training and high weekly mileage, and label them for what they are: elite practice, untested.

The lactate meter problem

The method’s appeal is precision: hit an exact lactate number. In practice, that precision is shaky.

• Portable lactate analysers carry a typical error of 0.4–1.0 mmol/L (Tanner and colleagues, 2010).
• Running at a speed meant to give 2 mmol/L produced actual values from 1.9 to 3.8 mmol/L (Fleckenstein and colleagues, 2023).

So a fixed target copied from a book may land you in a very different zone. If you use a meter, set targets from your own tested curve. See is Zone 2 overrated? for more on fixed lactate numbers, and how to set your heart-rate zones for simpler options.

The part that is well supported

Strip away the threshold details and the Norwegian model is still mostly easy running at high volume. That part fits the wider evidence well. See how much of your running should be easy and polarized vs pyramidal training.

Note also that Bakken and Copeland, two of the method’s book authors, sell the methods they describe, and three Norwegian-method books appeared in about 14 months.

What we don’t know

• No controlled trial has compared the Norwegian method with other approaches.
• No study has looked at marathon performance. The method was described in 1500 m and 5000 m runners.
• The right dose for amateurs is unknown. Elite runners doing 150–180 km a week are a poor guide for someone running 40.
• Whether double days beat the same work spread over separate days has not been tested for performance.

Sources

• Casado et al. (2023). Description of the Norwegian model of lactate-guided threshold training.
• Kjøsen Talsnes et al. (2024). Physiological strain of split vs single threshold sessions.
• Sandbakk et al. (2025). Interviews with Norwegian world-class endurance coaches.
• Grivas (2026). Comparison of East African and Norwegian training models.
• Seiler et al. (2013). Interval length and intensity in trained recreational cyclists.
• Marathon Handbook. Summary of Norwegian singles training.
• Tanner et al. (2010). Accuracy of portable lactate analysers.
• Fleckenstein et al. (2023). Lactate values when running at a fixed 2 mmol/L speed.