Mistake #2: Too Much VO2 Max Training

If you’re like me, you may have spent years following a training plan that contained a VO2 Max-type workout each and every week. Perhaps you still do – maybe you do them multiple times a week. They’re likely the hardest workouts in your 7-day cycle; the ones that most closely mimic the stress of a race – and you may look forward to them when you’re feeling great but dread them when you aren’t. When I use the term VO2 Max workout, I’m referring to interval sessions that usually involve 2-5 minute efforts at somewhere in and around 3-5k pace, typically with half the duration as a jog recovery (or less if the recovery is static). A classic might be 5 x 1k at 5k pace, with a 2-minute jog recovery. Sometimes these workouts may be longer and target 10k pace; and other times the repetitions may be shorter and target 1,500m or even faster, but they’ll always involve working above your anaerobic threshold and pushing your heart rate close to max for significant periods. 

After a 5-year break from running, I began again in 2014, and for 8 years these kinds of sessions were the focal point of my week. It took me a while to regain some consistency, but once I’d made it past those stutter steps, I saw significant improvements. After running a personal worst 45:20 for 10k in 2016, I ran 36:50 the following year. Now, much of this can be explained by simply running more. In the 12 months prior to running 45:20, I ran a grand total of 1150kms. In contrast, I ran 3900kms in the same period before running 36:50, and I’d strung together more than 12 months of training without any breaks due to injury. But during those 12 months, those higher intensity workouts seemed to work well – until they didn’t.

For 6 years, 36:50 remained my 10k personal best. Despite consistent training and a weekly schedule that seemed to follow what most of the trusted authorities in the sport suggested - a VO2 Max-type workout, a threshold workout, a long run and lots of easy running in between - I just couldn’t seem to improve. I ran roughly 80kms each week (not a lot, but a reasonable amount for a recreational runner) and stuck closely to the 80/20 rule (80% easy and 20% quality running). But despite regular strength and conditioning training, every time I tried to up my mileage, I would develop a niggle or something more serious. And so, my training volume remained quite flat. I had a few periods off due to injury in those 6 years, but each time I would return to full training, I would quickly plateau at around the mid to high 37-minute mark.

Kilometres Run by Year

 (2025 kilometres are projected based on current rate)

Year	2017	2018	2019	2020	2021	2022	2023	2024	2025*
Kilometres	3,895	3,648	2,036	3,043	3,853	2,646	3,697	4,915	5,463
10k PB	36:50	-	-	-	-	-	34:47	33:19	32:56

Like Boxer in Animal Farm, my maxim after every disappointing run during those years was “I will work harder”, when it should’ve been “I will do more”. The problem with working harder in any one session – I eventually realised - is it tends to prevent you from doing more. Starting in 2022, after my last serious injury, I began to experiment with ways to circumvent this issue. I started with cross training, which allowed me to do far more total volume of exercise. I worked up to consistently doing 10-12 hours of “aerobic exercise” per week, whereas when just running, I was maxing out at around 8 hours. Secondly, cross training allowed me to do more volume of intensity. That is, I began to (somewhat) imitate a “double threshold” day by doing a quality workout on the bike in the evening after I’d performed a running workout in the morning. For the next few years, I slowly introduced more running while reducing the amount of cycling, but I was determined to hold on to this large volume of intensity. This meant, I had to let go of the regular VO2 Max-type sessions. And so, I began to phase them out in favour of more and more threshold training, and guess what? It produced improvement after improvement. I’m now 35 years old and all of my personal bests from 3,000m up the marathon have been run within the past 13 months. My half marathon personal best in 2021 was 1:27:57, and just over a month ago (at the time of writing) I ran 1:14:23 – a 3 minute and 47 second personal best from my previous half marathon in July last year at the Gold Coast.

Like an addict, I can tell you that it’s been 10 weeks since my last VO2 Max workout and I don’t intend to do another one in the foreseeable future. I use the language of addiction because that seems to be the relationship runners have with high intensity training; it’s forged a psychological dependency, and we just can’t quit it for fear that we’ll somehow lose the ability to run at race paces. But that’s not how physiology appears to work. And in this article, I intend to explain why VO2 Max training may be the thing preventing you from consistently improving, and why other forms of training will likely produce better results for most runners, particularly at the recreational and club level.

The graph above displays the rise in the amount of threshold training I’ve performed over the past 5 and a half years. Starting in April 2022, I was averaging at least 3 cycling races per week on Zwift. For the most part, these races were done in a threshold zone, which meant that I was getting an additional 60+ mins of intensity each week through cross-training. This obviously had a profound training effect. From 2023, the amount of cycling gradually reduced until August 2024, when it was completely subsumed by running.

The graph above displays the number of VO2 Max workouts I’ve performed since 2020. I include the number of races due to the large VO2 Max component and stimulus of these efforts. The graph demonstrates how the amount of VO2 Max training I’ve performed has steadily decreased over time, which is inversely correlated with my running performances.

Now, I realise that I’m an experiment of one. There are certainly people out there who have achieved - and continue to achieve - great results (much better than mine) while frequently performing VO2 Max-style workouts each week. That’s fine. If you firmly believe that VO2 Max sessions are working for you and your results prove it, keep doing what you’re doing. But if you haven’t improved for a significant period while grinding out interval after painful interval, then maybe there’s something else for you. Ultimately, this article is for people who fall into the latter category. Hopefully, I can convince you that there’s nothing to fear in letting go of the hard workouts. And perhaps that feeling of resignation (which I most certainly had) – that maybe I’ve just maxed out my ability and I’ll never be able to get any faster – is a little premature.

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I’ll caveat by saying that the arguments I make throughout this piece are aimed at runners looking to improve at distances from 5k through to the half marathon (and perhaps even the marathon). Though I believe many of the recommendations would still benefit middle distance runners, they’re likely less relevant to athletes whose primary events last less than 5 minutes.

As mentioned, if you read all the popular training books – by some of the most trusted authorities in the sport - you’ll recognise that workouts targeting VO2 Max are among the most recommended. There’s a prevailing narrative in the running and fitness community that VO2 Max is the most important metric – and doing workouts at or close to this intensity is the best way to improve it (and improve distance running performance overall). However, other training approaches have surfaced in recent years that either demote VO2 Max from its central position in a training schedule or ignore it completely. The success of Jakob Ingebrigtsen at 1,500m and 5,000m has seen the spread of the “Norwegian Method” in which threshold training has assumed primary position, notably through the employ of regular “Double Threshold” days. A similar idea can be seen at the grass roots level with the “Norwegian Singles Approach”. Popularised on the website Letsrun, this method adapts the “Norwegian Method” to the time-crunched “hobby-jogger”, attempting to maximise the amount of “Sub-Threshold” running one can sustainably perform in a 7 to 8-hour training week (VO2 Max training excluded) (1). Though this approach hasn’t produced the highlights of the former, it’s been a pathway forward for many at the recreational level, most notably for its principal author, who in just 2 years has gone from a personal best of 18:50 in the 5k to running a 30:41 for 10k at the age of 41.

So if large improvements can be made and success at the highest levels can be achieved without regular VO2 Max training, why is VO2 Max training so ubiquitous?

First, let’s get a better understanding of what VO2 Max is:

According to Warner (2), “VO2 max measures how much oxygen your body consumes while exercising. Typically, VO2 max is measured as ml/kg/minute (milliliters of oxygen consumed per kilogram of body weight per minute of exercise).” We breath in oxygen, which gets transported from our lungs to our bloodstream. Red blood cells then carry the oxygen all around our body, specifically to muscle cells which require oxygen in order to produce their main energy source; ATP (adenosine triphosphate). Essentially, the more oxygen you’re able to breath in and absorb, the greater the potential for ATP production.

Therefore, having a higher VO2 Max is desirable for a distance runner, as that runner will have more oxygen available to distribute to his/her working muscles.

However, this is only part of the equation when it comes to distance running performance. As Jack Daniels (author of Daniels’ Running Formula) points out, “Just as some cars use less fuel to cover any particular distance of movement, so do some runners consume less oxygen” (3).  Therefore, VO2 Max, while desirable, doesn’t tell us anything about how efficiently our muscles use the supply of oxygen. The classic example given is that of Lance Armstrong, who reportedly had a VO2 Max of 83 ml/kg/min – a score with a predicted time of 2:03:45 for the marathon (according to at least two different conversion sites – 4, 5) – and yet, despite access to some of the world’s best running coaches, Armstrong was only able to achieve a time of 2:46:43 (6). For further reference, Frank Shorter’s VO2 Max was reportedly 71.3 ml/kg/min (7), and yet this didn’t prevent him from winning Olympic gold in the marathon and running a 2:10 on multiple occasions in the 1970s.

The reason? VO2 Max isn’t the only game in town.

There are other factors to consider, such as:

Running Economy - Daniels’ concept of “velocity at VO2 Max” (vVO2) provides a demonstration. In his example, two athletes may run at the same pace, but one uses far more oxygen to do so than the other. To go back to the previous example, Lance Armstrong may have had terrific economy on the bike, but his running economy was poor in comparison, and as a result, he required far more oxygen than Frank Shorter to sustain a given pace while running.

Other factors include an athlete’s Lactate Thresholds, which are vital for fractional utilization; in other words, an athlete’s ability to maintain intensities close to VO2 Max for long periods of time. There are two points on a lactate curve that are of primary interest: the instant at which lactate rises above baseline (known as LT1) and the point at which lactate breaks out of a semi-steady state and exponentially rises (known as LT2). Athletes remain far more efficient while running below LT2 (and even more efficient below LT1) as they’re primarily using oxygen to produce ATP rather than relying on a heavy contribution from the Glycolytic System (an anaerobic energy source). The rate of Glycolysis drastically increases above the anaerobic threshold in order to meet the greater energy demand, but this unsustainable energy source has the added drawback of significantly increasing the rate of fatigue (8). Therefore, the closer an athlete’s LT1 and LT2 are to their VO2 Max, the larger the contribution of (sustainable) aerobic energy at higher paces, which profoundly enhances performance at all endurance events.

There are other factors, of course (durability and nutrient metabolism spring to mind, particularly for events over 2 hours), but VO2 Max, Running Economy and Lactate Thresholds tend to be the big three metrics of distance running performance.

That’s all well and good, but doesn’t it show that we still need a high VO2 Max if we’re to maximise our performances? Wouldn’t the ideal scenario be a high VO2 Max in combination with excellent running economy and lactate thresholds? Therefore, don’t we still need to train our VO2 Max?

Perhaps, but training at VO2 Max may not be as productive as many are led to believe. For starters, the methods/workouts people traditionally employ aren’t as effective as other less common workouts.

According to Daniels an athlete “can run at VO2 Max for about 11 minutes”. Other accounts suggest it’s between 6-10 mins, but this gives us an approximate idea of the intensity at which VO2 Max occurs. Because of this, the assumption is that running at or very close to this intensity will provide the best VO2 Max stimulus. For many, this means roughly 3-5km race pace. The Norwegian 4 x 4 Protocol (Yes, another Norwegian method) is quite possibly the best example. Used across multiple sports, “this method involves four intense four-minute intervals at 90-95% of your maximum heart rate, each followed by a three-minute active recovery period. Backed by scientific research, the 4x4 Protocol is renowned for significantly boosting VO2 max, a critical measure of aerobic capacity” (9). For recreational runners, this might translate to a workout of 4 x 1k with a 3 minute walk or jog recovery; for club runners, 4 x 1200m; and for elite males, something close to 4 x 1 mile.

Similar workouts are also staples in the running world. Daniels, for example, prescribes the workouts below for 5k to 10k training:

·      4 x 1,200m with three minutes jog recovery.

·      6 x 800m with 400m jog recovery.

·      6 x 1k with 400m jog recovery.

Daniels calls this “I Training” (I for Interval) and explains that “the typical races associated with the I zone are in the range of 2 to 5 miles (3km to 8km)”. He then writes that the purpose of these workouts “is to maximize aerobic power (VO2max), and believing that the best way to improve any bodily function is to stress that function, I decided that the intensity had to be at or very close to VO2max (and maximum heart rate) …”

It’s hard to ignore the words “believing” and “I decided” in that description. It points to the notion that much of the training conventions around VO2 Max are based on rationalism rather than empiricism. In other words, they’ve not been tested and proven.

But research by Steven Seiler, among others, reveals that both the Norwegian 4 x 4 Protocol and Daniels-type workouts are not the most effective for improving VO2 Max. In a 7 week study carried out on trained recreational cyclists, which compared 4 x 4 minute intervals with 4 x 8 minute intervals and 4 x 16 minute intervals, the 4 x 8 minute workout was found to have the best outcomes for boosting VO2 Max. The reason being, “accumulating 32 min of work at 90% HR max induces greater adaptive gains than accumulating 16 min of work at ∼95% HR max despite lower RPE” (10). That is, although the 4 x 8 minute intervals were done at a lower intensity (90% HR Max) compared with the 4 x 4 minute intervals (95% HR Max), the 4 x 8 minute intervals were still intense enough to elicit a VO2 Max response, and the sheer volume of the workout provided a much stronger stimulus for adaptation. This indicates that volume of intensity is an important factor in developing aerobic capacity. It’s also worth pointing out that in well-trained athletes, 90% HR Max tends to coincide with the anaerobic threshold.

However, another case study completely de-emphasises the role of high intensity workouts as a prime mover for VO2 Max enhancement. Exercise physiologist and triathlon coach, Alan Couzens, details his use of high volume, low intensity training which improved one athlete’s VO2 Max from 53 ml/kg/min to 74 ml/kg/min. This athlete had already been training for many years using a more traditional low volume/high intensity approach, and yet, after switching to a high volume/low intensity training system, was still able to improve his VO2 Max by 40%. This, while reducing the amount of VO2 Max-type training (11). Couzens’ cites a study by Berbalk as his rationale for employing this strategy, which showed an “observed relationship between training volume and cardiac stroke volume, one of the most important and modifiable factors in VO2 max. In a large EKG study of athletes’ heart morphology, Berbalk discovered a strong, almost linear, relationship between training volume and total heart volume” (12). Couzens goes on to state, “the total volume of the athletes’ hearts, scaled not with the intensity of training, but with the average weekly volume! This makes good physiological sense, since we know that for the majority of people, stroke volume reaches its maximum limit at relatively low intensities of training (~40-60% VO2 max)”. Couzens suggests that the best way to increase stroke volume is by large volumes of training in this 40-60% VO2 Max range. For runners, that means lots and lots of very easy running over a long period of time.

The graph above (Berbalk) displays an almost linear relationship between overall training volume and cardiac volume.

If you look closely, you can see the scale along the x axis begins at 12 hours of training per week. With the exception of elites, the vast majority of runners aren’t getting close to this amount of training. And yet, we can see in this study that cardiac volume almost quadruples from 13 hours per week to 20 hours per week. Therefore, we must conclude that the gains are potentially enormous if we’re able to get our overall volume up into this range. As runners, there’s obviously a limitation caused by the high impact nature of the activity, but we need not add a further limitation in the form of overly taxing, low volume workouts that prevent us from getting close.

A similar conclusion was reached by Barbosa et al. In a study on 120 amateur runners, in which training volume was increased by an average of 32% across a 10 week period, VO2 Max was improved by 10.44% (13). These findings, along with Couzens’ and Berbalk’s, run counter to the popular belief, put forward by Daniels and others, that the best way to improve VO2 Max is to run at or close to VO2 Max. To quote Couzens, VO2 Max-type workouts are simply the “icing on the cake”. The obsession and overuse of VO2 Max workouts in a year round 7-day cycle sets runners up to scratch and claw for what Couzens estimates to be a 6% potential improvement in VO2 Max. Whereas, an approach that prioritises total training volume (which will likely reduce VO2 Max workouts out of necessity) can improve VO2 Max by up to 40%.

However, what might explain so much of the allure with VO2 Max workouts is that this 6% improvement can be achieved quite quickly. Athletes will commonly start a VO2 Max training regime, experience a sudden improvement, and then be hooked. They’ll continue with this type of training, either with the hope that it’ll produce the same improvements that it did before – or through fear that they’ll lose the gains they’ve made.

But, as demonstrated by the training of elite athletes, continually performing these kinds of high intensity workouts will soon lead to diminishing returns and eventually regression. That’s why the vast majority of elites periodise their training throughout a yearly cycle. As Haugen at al. found in a study conducted on 59 of the world’s greatest ever distance runners (including Kenenisa Bekele, Haile Gebrselassie and Sifan Hassan to name a few), elite long distance runners “typically divide the training year (macrocycle) into distinct, ordered phases (meso- or micro-cycles) with the explicit goal of peaking for major competitions” (14). These phases include the preparation phase, competition phase and the transition phase (post-competition recovery, etc.). The preparation phase (commonly referred to as the “base phase”) is typically divided into two segments: starting with general preparation and followed by specific preparation. The general preparation period involves an emphasis on high volumes of running in order to build an “aerobic foundation.” As athletes shift into the specific preparation period, the emphasis gradually moves towards higher amounts of race-specific intensity. But as Haugen reveals, elite track runners “are careful not to overuse race-pace training or introduce it too early in their annual cycle.”

Elite runners and their coaches understand that the gains from VO2 Max training (roughly race pace for 3-10k) are short-lived. An athlete will use these kinds of workouts in order to peak for a goal competition. Why? Because there’s actually a trade-off between aerobic and anaerobic development. As Borg writes, if you “pursue anaerobic training year-round, you will, at best, create a performance plateau as your aerobic and anaerobic energy systems “eat into each other”. It is a bit like constantly taking a few steps forward only to take a few more backwards. You won’t be going very far in the end” (15). VO2 Max, while a measure of aerobic capacity, is above the anaerobic threshold and therefore has a pronounced anaerobic component. In these workouts, a build-up of acidosis lowers the pH in the working muscles. “This acidosis starts a cascade of unwelcome events within your body including the sabotaging of the aerobic enzyme system on which your base fitness is built.” For elite runners, having a strong anaerobic system is obviously a necessity, given the nature of championship racing. Being able to change gears to stick with an ever-increasing pace in the final kilometre and then kick hard on the last lap is how medals are won. But this obviously comes at a cost to the aerobic system, and so a balance must be struck. A VO2 Max/anaerobic training block must be timed so that the goal race can take place at the moment of greatest upswing in anaerobic capacity, but before a decrease in aerobic capacity leads to a reduction in overall performance. This is called “peaking”.

Note: Obviously, not all VO2 Max workouts are made equal. Some are performed at 90-95% and will therefore have less of an anaerobic component (and involve less of the negative consequences listed above), while others will be at 100-105% and have more. The problem with VO2 Max workouts (as they’re prescribed to amateurs) is there isn’t a whole lot of intensity control. Therefore, who’s to say if a VO2 Max workout is performed at 95% or 105% of VO2 Max?

This level of sophistication seemingly hasn’t reached the recreational level yet though. Coaches continue to prescribe VO2 Max workouts year round, either for logistical or ideological reasons - or just through plain ignorance. As previously suggested, VO2 Max workouts are painful, mentally and physically demanding and can often be demoralizing. When we add to the equation that they’re likely also diminishing an athlete’s aerobic development (if performed too often), it seems illogical to include them in a constant 7-day cycle. And yet, people still line up to perform them each and every week, regardless of the improvements (or lack of) this type of training seems to produce.

So if we shouldn’t do VO2 Max training year round, what can we do instead?

Lydiard’s approach was to solely focus on building mileage throughout the winter months (100 miles per week became the benchmark). In this period, all runs were performed below the aerobic threshold (LT1) in the easy to steady range (Zone 1 and 2 for those who prefer HR Zones). This proved to be extremely effective for the athletes he coached, but for the hobbyist, who likely doesn’t have distinct racing seasons, this approach may not be fit for purpose. That’s not to say that amateur athletes won’t benefit from a base period, but as mentioned earlier, a couple of fully formed training systems have recently surfaced that may offer a more manageable (and enjoyable) blueprint for how to train in this phase – and potentially for most of the year.

The Norwegain Method – or what is sometimes referred to as the “Norwegian Double Threshold System” - is one such approach. Now, I’m not recommending that everyone should go out and start doing double threshold days, but the principles of the system give us an insight into the energy systems we can develop during this phase without the elevated risk of burn-out or stagnation. Rather than simply performing long easy to steady runs, the Norwegian Method focusses, to a large extent, on threshold running.  

Below is the frequently circulated example of the Norwegian Method during the winter/base training schedule (and for most of the year). This is the program followed by current and former athletes such as Jakob Ingebrigtsen, Narve Nordas, Andreas Almgren and Kalle Berglund to name a few.

	AM	PM
Monday	10km Easy Run	10km Easy Run
Tuesday	Threshold: 5 x 6’ @ ~2.5mmol. 60-90” recovery.	Threshold: 10 x 1k @ ~3.5mmol. 60” recovery.
Wednesday	10km Easy Run	10km Easy Run
Thursday	Threshold: 3 x 10’ @ ~2.5mmol. 60-90” recovery.	Threshold: 20-25 x 400m @ ~3.5mmol. 30” recovery.
Friday	10km Easy Run	10km Easy Run
Saturday	Hills: 2 x 10 x 200m. Jog back recovery (~70”) and longer between sets.	10km Easy or “Outwash” (which is 6 x 1k @ the same intensity as Tue/Thu morning sessions)
Sunday	20km Easy Run	Rest
Total Weekly Volume	175-180kms

In this schedule, we can see that the amount of threshold running can total as much as 46 kilometres per week (for a world-class male athlete). The rationale for this heavy threshold focus is provided by Marius Baken (creator of the system):

“The limiting performance factor for most 5k/10k runners is the anaerobic threshold. Speed matters but I believe a common flaw in the thinking is that the most specific way of training is doing work at race pace or sub-race pace.

Yes, from a purely mechanical standpoint this seems like a smart approach. In theory, it sounds natural to train at a speed that you need to perform at when racing.

However – the mechanical “speed” you are running will always at one point or the other be majorly limited by the aerobic abilities, where the ability to run at a maximum speed at the anaerobic threshold is the main one.

So specific training from a more physiological standpoint, where you optimize the internal cell processes…is not at race speed…Rather it is a combination of larger amounts of lactate threshold work with a fair level of total running, which was in my case about 180 km weekly running.” (16)

In other words, given that the energy demands of the 5,000m and 10,000m are in excess of 94% aerobic (17), the most specific ways to train, metabolically, are at paces one can sustain without heavy anaerobic contributions (such as those provided by Glycolysis). By training just below the anaerobic threshold, an athlete is able to do far greater volumes of intensity, as they’re avoiding the byproduct dump that accompanies higher intensity anaerobic efforts. This byproduct significantly delays recovery. As Borg writes, after performing exercise with a heavy anaerobic component “it can take 24 to 96 hours for your system to settle back to normal but recovery can take longer.” Magness reinforces this idea by stating, “…the common understanding is that the immediate system and Glycolysis lead to some negative drawbacks like by-products” (18).

Bakken appears to have figured this out through a long process of trial and error, and with the assistance of a lactate meter. He found that “staying from 2.3 (mmol) up to 3.0 on sessions gave not only far better results, you could also do huge amounts of “threshold training””. And this is what I would argue is the essence of the system (or at least 1 of the 2 pillars – the other being “overall volume”); the emphasis on total volume of threshold. This idea is reiterated by Simen Halle Haugen (a Norwegian 5,000m runner) who states that for athletes who follow this system, the aim is to build up to doing as much threshold training in the week as possible (19).  

But what’s so special about threshold training?

Well, according to Pfitzinger, it has a lot to do with mitochondria – “the aerobic energy factories in your muscle fibers”. He states that “by fully utilizing your ability to produce energy without accumulating high levels of lactate, lactate-threshold training increases the size of your mitochondria (i.e., makes bigger factories) and the number of mitochondria (i.e., makes more factories) in your muscle fibers. With more mitochondria, you can produce more energy aerobically and maintain a faster pace” (20). So, by replacing your VO2 Max workouts with threshold training, you:

*     enhance rather than degrade your aerobic system

*     avoid much of the fatigue that accompanies high intensity training (and the injury risk)

*     can perform much greater volumes of quality running – which offers a far greater signal for adaptation

But how do I get faster if all of my “speed” work is done at 1 hour pace?

This appears to be a very common misunderstanding. The anaerobic threshold, in this context, is not defined by pace. It’s a metabolic state, where the amount of lactate in the blood has risen above base levels, but is being cleared before the buildup can accelerate significantly. Here, lactate is a proxy for the rate of Glycolysis. Bakken found that this 2.3 – 3.0mmol figure was his own personal “sweet spot”, but this didn’t mean that he was simply doing continuous runs at intensities that produced figures in this range. By breaking up the effort into repetitions, with short rests in between, he was able to run at a higher pace while remaining below this 3.0mmol figure.

If we zoom in on the training schedule listed above, we can see that on Thursday evenings, athletes perform a workout of 400m repetitions. In a paper co-authored by Marius Bakken, the authors claimed to have witnessed sessions being performed by “international level distance runners” of 20-25 x 400m with a 30 second recovery. In these workouts, certain athletes were able to average 64 seconds (13:20 pace for 5k) for each repetition, while staying below the anaerobic threshold. In another example of 20 x 400m, this time with a 60 second recovery, certain athletes were able to average 62 seconds (12:55 pace for 5k). This is well in excess of the crude but popular AT definition of “1 hour pace”. The authors explain “the reason why this can be achieved is that duration of the running time/distance is too short for blood lactate to rise above LT2, and the rest period between repetitions is long enough for blood lactate to return to levels near LT1 but not long enough to decrease under that threshold” (21).

But what about the Saturday hill session, isn’t that a VO2 Max workout?

Well, if it is, it’s not a very good one. For one, the duration of each repetition (30-35 seconds) is very short. When we combine this with the length of the recovery (~70 seconds), then it’s unlikely that a significant amount of time is being spent in what could be termed a “VO2 Max zone”. According to Brad Culp (author of The Norwegian Method), Jakob (Ingebrigtsen) “claims that he aims for 87% effort throughout all 20 reps. That equates to roughly a 5k effort on each rep – note that’s effort, not pace” (22). If true, then it’s unlikely Jakob is crossing the anaerobic threshold; given that on the Thursday evening sessions he’s able to perform ~60 second reps at around 5k effort, with less recovery, while remaining below AT. However, other accounts (including Bakken himself) claim that Jakob aims for a lactate reading of 7-10mmol during the hill reps, which is well above the anaerobic threshold.

And so, I concede that this appears to be more intense than a threshold workout, but it’s likely a necessary compromise for an elite track athlete. Despite winning the past 3 global titles at 5,000m, Jakob is primarily a 1,500m runner (so too Nordas and Berglund), and therefore, maintaining a powerful stride and running economy at close to top speed is of utmost importance. Being able to finish with a last lap of 52 seconds is now almost a prerequisite for gold in both the 1,500m and 5,000m. But we can see that much has been done to minimize the stress of these efforts: the reps are short, the recovery is long, and they’re performed on a hill to lessen the impact. This is all done with the intention of decreasing the recovery time following such an effort.

But do we, as amateur runners, need to include these kinds of ‘above AT workouts’ in our own weekly schedule? Or would we be better served to simply add more threshold training?

Well, this leads me to the Norwegian Singles Approach. Dubbed “the Norwegian Method for hobby-joggers”, this system dumps the hill workout (and all running above AT) while also aiming to maximise the amount of threshold training one can sustainably perform each week. It’s intended for amateur runners who are looking to get the most “bang for their buck” out of an approximate 7-8 hour training week and emerged on the now 250+ page Letsrun thread, titled, “Modifying the Norwegian Approach to Lower Mileage”. It’s author, who goes by the username “sirpoc84” (and for reasons of privacy, we will refer to as Sirpoc from here on in) explained how he’d been observing Kristoffer Ingebrigtsen’s training on the website Strava. Kristoffer is an older sibling of the elite Ingebrigtsen trio and is also an amateur runner himself. Sirpoc deduced that if Kristoffer’s training was being provided by his father and brothers, then it would be a boiled down version of the “Norwegian Method”; that only the most essential training would be kept – at least, for a recreational runner looking to improve his times at distances from 5k through to the half marathon. He noticed that rather than doing the now famous “double threshold” workouts and the hill workout, Kristoffer would do 3 single interval workouts per week, all within the threshold range (between LT1 and LT2). The remaining runs included a long run of roughly 90 mins and easy runs of around 1 hour on the remaining days. This served as a template for how best to implement the principles of the Ingebrigtsen approach on a greatly reduced schedule. For someone working a full-time job, with other commitments, this is obviously an incredibly pragmatic training system.

An example training week for someone running 7-8 hours per week is below:

Monday	50-60 mins easy
Tuesday	10 x 3 mins @ ~15k pace (60” recovery) Plus warm up and cool down = 60 mins total
Wednesday	50-60 mins easy
Thursday	5 x 6 mins @ ~HM pace (60” recovery) Plus warm up and cool down = 60 mins total
Friday	50-60 mins easy
Saturday	3 x 10 mins @ ~30k pace (90” recovery) Plus warm up and cool down = 60 mins total
Sunday	90 mins – 2 hrs easy

The system isn’t designed to be a base period (though it can function as one) but rather a year-round 7 day cycle. Easy runs are performed at 70% Max HR or 65% MAS. Lactate testing is recommended initially, but not a requirement. The instruction is to be conservative with paces at first (particularly if not using a lactate meter). A website that prescribes paces based on recent race results can be found in the additional resources section at the end of this article.

But why opt for this training system rather than a more traditional “Daniels-style” approach?

Well, similar to my own experience, Sirpoc states at the beginning of the thread:

“I had stagnated around 18:5x for quite a while for a 5k but have now made quite a big jump recently to 17:27” (23).

Coming from a cycling background, Sirpoc recognized the similarities between Kristoffer’s training and what is commonly referred to as sweet-spot training in cycling. Sweet-spot training targets the highest intensity that can be performed frequently in relatively large volumes. “This type of work achieves positive physiological adaptations because it is the optimal balance of difficulty (intensity) and amount (volume)” (24). Sirpoc goes on to claim:

“in terms of overall training load it also creates more CTL [Chronic Training Load] for about the same amount of time on feet compared to training more traditionally, which I had tried (I'd read Daniels, faster 5k and a couple of others)”.

If you’re not familiar with CTL, it’s a way of calculating the accumulation of training in a rolling period, taking into account volume and intensity. It’s very popular in cycling, where tracking one’s training load is done religiously (even by amateur cyclists), but as runners, we tend to be very poor at accounting for training load (outside of counting kms or miles) - and I’d argue that this is part of the reason why injury rates in running are so high.

But to return to Sirpoc, he goes on to state:

“because there is very little vo2 max stuff I pretty much am ready to go for the next session no problem. Also feel way less tired running this way.”

By sticking to this sweet spot that he calls “sub-threshold”, he is able to perform a much greater volume in his workouts and is then able to back up again 48 hours later to carry out another “sub-threshold” session. He found that when including higher intensity training, such as the one’s prescribed by Daniels, not only was he unable to do nearly as much in each individual session, he also wasn’t able to recover in a manner that would allow him to sustainably fit 3 workouts into a week. Therefore, when following Daniels-style training, his training load was lower, with a higher perceived level of fatigue, compared to the sub-threshold approach.

Now, an improvement from 18:50 to 17:27 in the 5k is great, but it’s hardly Earth shattering. However, this was just the start. At the time of his initial post, Sirpoc was 39 years old and had only been following this system for a few months. I can now tell you that he’s 41 and his personal bests have improved to:

5k: 15:01

10k: 30:41

Half Marathon: 1:08:50

Marathon: 2:24:08

And given that the marathon time was run at London this year (in warm conditions, where many notably underperformed), it may just be the best performance of the lot. Regardless, the progression is mind-boggling. If you’ve been running for a long time, you’ll understand just how phenomenal that trajectory is. For reference, his average 5k pace during the London marathon was 17:04, a whole 23 seconds faster than his all-out 5k time of 2 years earlier (and 1:46 faster than his 5k under the Daniels approach). With that level of improvement, you’re not just a better runner, you’re a different species of athlete.

So, why does this system work better than the more traditional approach?

Well, it’s ultimately a numbers game.

Traditional models (while professing to be holistic systems) tend to be rather hodge-podge collections of different stimuli that aim (or hope) to add up to a more physiologically rounded athlete. They tend to prescribe a bit of speed endurance, a bit of VO2 Max, a bit of threshold, a bit of tempo, some steady running and a good amount of easy miles. Maybe it gives the authors of these systems an opportunity to put more chapters in their books - or provides the appearance of “balance” – but it just leads to programs that include a bit of everything, while maximizing nothing. In addition, these systems not only place greater weighted emphasis on intensities above the anaerobic threshold, but they also create a situation in which there are too many variables to accurately calculate training load. And so, athletes end up metabolically undertrained while mechanically overtrained and eventually stagnate, burn-out or get injured. As previously mentioned, events from 5k and up are in excess of 94% aerobic, and yet, when following these approaches, athletes spend so much of their available training load working on the 6%, at the expense of the 94. When we view it like this, we can see that a schedule that includes frequent workouts above the anaerobic threshold is not at all balanced, but rather lopsided.

But the Norwegian Singles Approach demonstrates that what actually matters (for long term development) is fitting the maximum physiological stimulus into a cycle that can be repeated week after week without breaking down. Traditional approaches do a poor job of this because they refuse to unshackle from specificity and outdated notions involving VO2 Max and speed. Ultimately, these are all impositions that frustrate our development, rather than progress it. But if we stick to the numbers and maximise our CTL, we place ourselves in the best possible position to provoke running specific adaptations for distance events.  

Additionally, the sentiment echoed throughout the Letsrun thread is very similar to the one championed by Arthur Lydiard 60 years ago; that the major limiting factor for distance running performance is an athlete’s capacity for aerobic metabolism. That is, the ability of the working muscles to convert “oxygen to energy” (25). And this is even more the case with recreational runners. The limiting factor is very rarely speed. You see this play out every weekend, at every parkrun or road race around the world. Runners will take off at a much faster pace than they can sustain. The pace feels easy at first while they’re relying on the immediate system and Glycolysis to meet the energy demand. But once they get ~90 seconds in – and their aerobic system largely takes over – their brain reassesses the situation and forces them to slow down. It recognizes that the effort is unsustainable for the distance, because their aerobic system simply isn’t up to the task.

The Norwegian Singles Approach effectively says - we’re going to get more benefit by addressing this weakness, and turning it into a strength, than by assigning precious training time to other physiological parameters.

Most of us aren’t looking to win championship races with a last lap kick. We’re simply trying to hold faster and faster paces for long distances. Therefore, training our bodies to more efficiently utilise oxygen is going to provide us with the most benefit for the limited amount of mechanical load we can handle and the training hours we have available to us. By dumping the VO2 Max intervals – for at least part of the year - we effectively remove the roadblock and free up significant space for training that provides a better aerobic stimulus.

To be continued.

References:

1.     ‘Modifying the Norwegian Approach to Lower Mileage’. LetsRun. July 24, 2023. https://www.letsrun.com/forum/flat_read.php?thread=12130781 Accessed May 24, 2025.

2.     Warner, Lindsay. ‘VO2max: What Is It and How Can You Improve It?’. Harvard Health Publishing, Harvard Medical School. July 8, 2024. https://www.health.harvard.edu/staying-healthy/vo2-max-what-is-it-and-how-can-you-improve-it  Accessed May 24, 2025

3.     Daniels, Jack. 2014. Daniels’ Running Formula: Third Edition. Human Kinetics. Champaign, IL. pp. 33-34, 57, 181-183.

4.     Reverse VO2 Max Calculator. Runbundle. https://runbundle.com/tools/vo2-max-calculators/reverse-vo2-max-calculator  Accessed May 26, 2025

5.     Effective VO2 Max. Runalyze. https://runalyze.com/tools/effective-vo2max?vo2max=50.00&units=km&paces=1  Accessed May 26, 2025

6.     ‘Lance Armstrong Clocks Impressive Marathon Time: Former Cyclist’s Surprising Performance’. Mount Bonnel. https://www.mountbonnell.info/lances-austin/lance-armstrong-clocks-impressive-marathon-time Accessed May 26, 2025

7.     Fitness Testing Records: VO2 Max Test Records. Fitness Testing. https://www.fitnesstesting.com/records/vo2max-test.htm  Accessed May 26, 2025

8.     Parnell, Karen. ‘Maximising Your Endurance: How to Train at Your Threshold’. Chili Tri. May 2, 2023. https://www.chilitri.com/blog/karenparnell01@hotmail.com/maximizing-your-endurance-how-to-train-at-your-threshold  Accessed My 26, 2025

9.     ‘Boost Your VO2 Max and HR Max with Norwegian 4 x 4 Protocol’. Norwegian 4x4.  https://norwegian4x4.com/#:~:text=This%20method%20involves%20four%20intense,critical%20measure%20of%20aerobic%20capacity.  Accessed May 26, 2025

10.  Seiler, Stephen, et al. Adaptations to Aerobic Interval Training: Interactive Effects of Exercise Intensity and Total Work Duration. Scandinavian Journal of Medicine and Science in Sports. Vol. 23, No. 1. 2013. pp. 74-83.  https://pubmed.ncbi.nlm.nih.gov/21812820/  Accessed May 26, 2025

11.  Couzens, Alan. ‘How Trainable is VO2 Max Really? A Case Study. Simplifaster. https://simplifaster.com/articles/how-trainable-is-vo2-max/

12.  Berbalk, A. “Echokardiographische Studie zum Sportherz bei Ausdauerathleten” in: Zeitschrift fur Angewandte Trainingswissenschaft. Vol 4. pp 34-64. 1997. Aachen: Meyer & Meyer

13.  Barbosa, Rhennan Rodrigues, et al. ‘Effect of Aerobic Training Volume on VO2max and Time Trial of Runners: A Systematic Review’. Journal of Human Sport and Exercise. Vol. 19, No. 4. 2014. https://www.jhse.es/index.php/jhse/article/view/aerobic-training-volume-runner-performance  Accessed May 26, 2025

14.  Haugen, Thomas, et al. ‘The Training Characteristics of World-Class Distance Runners: An Integration of Scientific Literature and Results-Proven Practice’. Sports Medicine – Open.Vol. 8, Article 46 .2022.  https://pmc.ncbi.nlm.nih.gov/articles/PMC8975965/#Sec4  Accessed May 26, 2025

15.  Borg, Rene. ‘Why You Don’t Do Anaerobic Exercise During the Aerobic Phase’. Champions Everywhere. September 21, 2011. https://www.championseverywhere.com/why-you-dont-do-anaerobic-during-the-aerobic-phase/  Accessed May 26, 2025

16.  Bakken, Marius. ‘The Norwegian Model of Lactate Threshold Training and Lactate Controlled Approach to Training: A Look at Some of the Concepts, History and Keys to Improvement. Marius Bakken. https://www.mariusbakken.com/the-norwegian-model.html  Accessed May 26, 2025

17.  Davis, John. ‘Individual Variation in Aerobic and Anaerobic Contributions to Different Events’. Running Writings. January 19, 2025 https://runningwritings.com/2025/01/aerobic-vs-anaerobic-contributions-in-running.html  Accessed May 26, 2025

18.  Magness, Steve. (2014). The Science of Running: How to Find Your Limit and Maximise Your Performance. Origin Publishing. pp. 29

19.  Halle-Haugen, Simen. In, Jones, Callum, host. ‘Simen Halle-Haugen on the Norwegian System’. Conversations About Running Podcast. 2022. https://www.traininkenya.com/podcast/ 

20.  Pfitzinger, Pete. Douglas, Scott. Advanced Marathoning: Second Edition. Human Kinetics. Champaign, IL. pp. 7

21.  Casado, Arturo, et al. ‘Does Lactate-Guided Threshold Interval Training within a High Volume Low Intensity Approach Represent the “Next Step” in the Evolution of Distance Running Training?’. International Journal of Environmental Research and Public Health. Vol. 20, No. 5. 2023. https://www.mdpi.com/1660-4601/20/5/3782  Accessed May 27, 2025

22.  Culp, Brad. ‘Norwegian Method Hill Workouts’. Eighty Twenty Publishing. May 8, 2025. https://8020books.com/norwegian-method-hill-workouts/#:~:text=For%20Jakob%20Ingebrigtsen%2C%20the%20hill,muscular%20strength%20while%20minimizing%20impact.  Accessed May 27, 2025

23.  Sirpoc84. ‘Sirpoc84 Posts’. Sub-Threshold.  https://sites.google.com/view/sub-threshold/sirpoc84-posts  Accessed May 27, 2025

24.  Hurley, Sean. ‘What is Sweet Spot Training: Everything you Need to Know’. Trainer Road. https://www.trainerroad.com/blog/sweet-spot-training-everything-you-need-to-know/  Accessed May 27, 2025

25.  Lydiard, Arthur. In, Moller, Lorraine. ‘Lydiard Training Principles’. Lydiard Foundation.  https://www.lydiardfoundation.org/about-us#:~:text=Think%20of%20aerobic%20running%20as,to%20respond%20and%20recover%20quickly.  Accessed May 27, 2025

Additional Resources:

26.  Prescribed Paces for Norwegian Singles Approach: https://lactrace.com/norwegian-singles