Norwegian singles are transforming how distance runners approach threshold training, and they might be exactly what your running program needs.
This sub-threshold interval method promises remarkable aerobic gains in just 6-8 weeks, all while reducing injury risk compared to traditional speed work.
Irish master’s runner Terry O’Hare recently shared his experience with this training approach, explaining both its Norwegian origins and practical application for everyday runners.
What makes Norwegian singles different from conventional interval training? The answer lies in volume, frequency, and control.
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What Are Norwegian Singles?
Norwegian singles are extended intervals performed at just below lactate threshold pace—what coaches now call “sub-threshold.”
While threshold intervals aren’t revolutionary, Norwegian runner Marius Backan took them to new extremes about 20 years ago. Backan, a 5,000-meter specialist, understood that running just below lactate threshold built exceptional aerobic capacity, but he faced a challenge: how could he accumulate more threshold work without courting injury or exhaustion?
His solution? Run them slower.
By reducing intensity slightly, Backan discovered he could perform threshold sessions more frequently—sometimes twice daily. Jakob Ingebrigtsen’s father and coach adopted these principles, and the Norwegian running dynasty was born.
Today, most elite distance runners incorporate double threshold sessions twice weekly or more into their schedules.
Making Elite Training Accessible
Most recreational runners can’t commit to double threshold days.
Full-time jobs, family obligations, and life’s demands make elite training protocols impractical. That’s where Norwegian singles enter the picture—a diluted version of double threshold training that fits reality.
The popular approach involves sub-threshold intervals three times weekly, a long run on Sunday, and filling remaining days with easy (or very easy) running.
How to Run Norwegian Singles
Finding Your Sub-Threshold Pace
Elite athletes often use lactate testing meters for precision, but this remains impractical for most runners.
Threshold pace is commonly described as a pace sustainable for roughly one hour at maximum effort. For most runners, that falls between 10K and half-marathon race pace.
Sub-threshold pace sits slower than threshold—typically around marathon race pace.
O’Hare provides specific examples: “Let’s say you’re a three-hour marathon guy, that’s 6:52 a mile, 4:16 per kilometer. Your 1K repeats are in and around that, a little bit slower.”
The Bread and Butter: 1,000-Meter Intervals
One-kilometer intervals form the foundation of Norwegian singles training.
If you’re accustomed to hammering out fast 400s until collapse, this will feel surprisingly slow. That’s intentional.
You need to be able to run the last one at exactly the same pace as the first one. And what’s more, you need to be thinking, I can do this all over again the day after tomorrow and all over again again two days after that.
The target is six to ten 1,000-meter intervals at sub-threshold pace. Control remains paramount.
Jakob Ingebrigtsen’s extensive lactate monitoring doesn’t tell him to speed up—it signals when to slow down.
Workout Variations
Running 10×1K three times weekly becomes monotonous, though it’s perfectly viable.
Keeping total volume around 10 kilometers per session, runners can vary workouts:
- 5×2K intervals (run 15 seconds per kilometer slower than 1K pace)
- 6×1 mile repeats (similar adjustment for longer intervals)
- 10×1K repeats (around marathon pace)
For that three-hour marathoner running 4:16/km pace, 2K repeats would clock in around 4:31/km (7:10/mile).
Marius Backan said it is infinitely better to run these 10 seconds too slow as opposed to 1 second too fast.
Recovery Intervals
Start with two-minute recoveries for 1K intervals, gradually reducing to 90 seconds, then one minute. Going shorter provides minimal additional benefit.
For 2K repeats, begin at 2.5 minutes, progress to two minutes, and eventually settle at 90 seconds.
The Conversation Test
While zone 2 training allows conversation throughout, sub-threshold pace sits differently.
O’Hare offers this practical gauge: After completing eight 1K intervals, if asked whether you could run two more:
- “Absolutely no way. I’m knackered. I’m on my knees.” — Too fast
- “Ah, no bother. When do I start?” — Too slow
- “Yeah, I could, but I really don’t want to.” — Perfect
Who Should Try Norwegian Singles?
Technically, anyone can attempt this training method.
However, O’Hare recommends building to approximately 40 miles weekly before incorporating Norwegian singles. That base provides necessary background strength for handling three quality sessions weekly.
Masters runners particularly benefit from this approach. They typically possess strong aerobic foundations and appreciate introducing speed work with lower injury risk compared to traditional interval training.
Real-World Results and Limitations
O’Hare tested Norwegian singles personally, committing fully to the protocol for several weeks.
I can honestly say that if you want to build a huge aerobic foundation, this will do it for you and quickly. 6 to 8 weeks of this will make an enormous difference to your aerobic capacity. I felt strong, strong, strong. Maybe the strongest I’ve ever felt.
The results were impressive: at 71 years old, O’Hare ran a 1:38 half marathon.
The Speed Work Gap
Despite remarkable aerobic gains, O’Hare identified one significant limitation.
Although I felt very, very strong, I didn’t actually feel that fast. I felt a bit one paced.
Reviewing Backan’s original work revealed a crucial element: Backan raced virtually every weekend, effectively adding serious anaerobic speed work weekly.
For half marathon and marathon distances, Norwegian singles work exceptionally well as standalone training. After all, you’re performing three weekly sessions at marathon-specific pace.
For 10K and 5K racing, however, supplemental speed work becomes necessary:
- 5×100-meter strides added to easy run days
- Hill sprint sessions incorporated weekly
- Regular race participation mimicking Backan’s approach
Building Sustainable Aerobic Power
Norwegian singles represent intelligent adaptation of elite training principles for everyday runners.
By prioritizing volume over intensity, consistency over heroics, and sustainability over suffering, this approach builds exceptional aerobic foundations with reduced injury risk.
The method requires patience and discipline—resisting the urge to push harder might prove more challenging than the workouts themselves. Remember Ingebrigtsen’s lactate monitoring: it’s there to enforce slowdown, not encourage acceleration.
For marathon and half marathon preparation, Norwegian singles deliver comprehensive training stimulus. Shorter distance specialists should supplement with targeted speed work, ensuring leg turnover matches aerobic capacity.
Whether you’re a master’s runner seeking sustainable intensity or a recreational athlete building toward longer distances, Norwegian singles offer a proven pathway to substantial aerobic improvement—no Norwegian heritage required.
