"The most significant advance in running training since the original interval training."

"Some say that New Interval Training is merely structured Fartlek on the track
- in many ways it is but it is much more than that."

Fartlek Training

Gusta Holmer

Gösta Holmér: Innovator of Fartlek - the 'Swedish natural method' of training

Fartlek training is a well known and a well respected training method that was first developed over 70 years ago, in the late 1930's, by the Swedish coach, Gösta Holmér and was introduced at about the same time that Gerschler and Reindel were experimenting with the original Interval Training. Fartlek training was designed as Holmér's response to the Swedish distance athletes' lack of success against the Finnish teams of the day, including the legendary Paavo Nurmi, and also to having limited access to specially built training facilities in Sweden at that time.

Gösta Holmér's Fartlek could be done virtually anywhere, even where there were no recognised athletics tracks. The word 'Fartlek' itself comes from the Swedish for 'Speed Play' and reflects that this training provides for a variety of speeds or paces combining continuous aerobic emphasis training with faster than race pace efforts. True Fartlek allows the athlete to run whatever distances and speeds they wish and to 'play' with varying the intensity, occasionally running at high intensity levels, occasionally at lower intensities. Varying the terrain for the Fartlek session merely added another variable to play with and Fartlek was frequently done through woods on undulating trails. This Fartlek training was also known as the 'Swedish natural method', or just the 'Swedish method', of training.

Girl Running

In the beginning a typical Swedish Fartlek session would comprise a total of 12 kilometres running with up to 5,000 metres of this running being at faster than race pace. And this Fartlek training would be done regularly and often, from three to five times a week. Holmér's athletes blossomed under the Fartlek regime and produced world records in all distances from two miles to 10,000 metres.

The most successful of these athletes was Gunder Hägg who in the summer of 1942 established ten world records over an 82-day period in seven different events, from 1500 metres to 5,000 metres. The running world took notice and word of the new 'Fartlek Training' spread.

Gundar Hagg and Arne Andersson

Gundar Hägg (leading) and Arne Andersson - exchanged the mile world record five times from 1942 to 1945

But Gunder Hägg was certainly not a one-summer wonder because from 1942 to 1945 he exchanged the world mile record an amazing five times with his Holmér-coached colleague, Arne Andersson. Together they owned the mile, taking the world record in a three-year period from 4:06.1 to 4:01.3, tantalisingly close to the magical 4-minute barrier.

One of the coaches taking notice during this time was the Australian, Percy Cerutty who embraced Fartlek in the 1950s as a vital component of his Portsea-based training near Melbourne. He combined beach running in heavy sand, sand dune training on dunes over 25 metres high with speed play over the undulating trails of the cliff tops, as well as on the flat beach and dirt roads. Cerutty was continually challenging his athletes to, "find the primal driving force within" while at the same time, "having fun running naturally" and Fartlek provided Cerutty with the solution to achieving these apparently paradoxical objectives.

Percy Cerutty shows Herb Elliott how it's done

Percy Cerutty shows Herb Elliott how it's done.

Herb Elliott was Percy Cerruty's best known athlete and was coached by him from 1956 to 1962, when Elliott retired at 23 years of age. In his relatively short career Elliott was undefeated at 1500 metres and the mile. In 1958 he won both the 800 and 1500 metres at the British Empire and Commonwealth Games in Wales and less than a month later broke the world mile record with 3:54.5 in Dublin, Ireland. In 1960 he went to the Rome Olympic Games and won the 1500 metres by 2.8 seconds, one of the largest winning margins, and setting a new world record of 3:35.6 in the process. Herb Elliott credited Percy Cerutty's coaching for his success, saying that he had inspired him "to train harder and more naturally" than anyone else of his era.

The success and effectiveness of Fartlek is well established and documented and provides observable physiological and psychological benefits but can it be made better? Can it be made more efficient, even more effective? Coaches and athletes have known that Fartlek produced results by blending intensities but 'knew' this intuitively and from results rather than from an understanding of what was happening inside the athlete. In the past 25 years we have learned so much more about metabolic energy production than in the preceding 100 plus years. We can utilise what we now know about how the energy systems function dynamically to improve how we do Fartlek, without destroying its essence.

A more Effective Fartlek with Lactate Dynamics Training

Click below to see types of Fartlek training
for optimal lactate dynamics development
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You will have already read on this website that Lactate Dynamics Training is any form of training where lactate production is deliberately increased by the intensity of exercise and then alternated with periods of less intense activity. In this way the muscle cells learn how to both use and clear the produced lactate during the less intense recoveries. The alternating lower intensity periods become a time when lactate usage for energy production and clearance rates can really be accelerated, provided that these running recoveries are not too slow.

You're probably thinking already, "alternating periods of faster running with periods of slower running" - but that sounds very much like Fartlek training. Well, you're right on the money. Properly done, Fartlek training is a classic form of Lactate Dynamics Training and trains the lactate shuttle in an environment away from the track. The problem is that the Fartlek done in clubs and by many athletes can be generalised as being too fast on the fast sections and too slow on the slower, recovery sections. This does not train the lactate shuttle very well. If the fast sections were not quite so fast, say varying from about 1500 to 3000 metres up to 10,000 metres pace within a 25-30 minute Fartlek, and the easier sections at 10,000 metres to half marathon and marathon pace, then the lactate shuttle would be better trained. The object is to accumulate some lactate and then in the active easier/recovery sections to both use it as fuel and to clear it.

When Fartlek is performed correctly it stresses the athlete for an optimal development of the synergistic relationship between the lactate and aerobic metabolic energy pathways. It is an incredibly powerful method for all endurance athletes to develop their natural rhythm and accompanying 'lactate dynamics' abilities away from the track.

"Understanding Lactate Dynamics Training means that we can design and perform better and more effective Fartlek, without losing the natural 'play' and 'fun' aspect."

I said at the beginning that, "Some say that New Interval Training is merely structured Fartlek on the track and in many ways it is but it is much more than that." Elsewhere on this website you will read how New Interval Training takes the physiological principles that we have used intuitively in effective Fartlek training and adds to it the development of pace and rhythm technique on the track. It can be difficult for an athlete to learn or develop these race pace rhythms without raising their awareness through accurate feedback and the track provides this environment.

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What did Gösta Holmér's Fartlek training achieve?

The two most successful athletes that Gösta Holmér coached were Gundar Hägg and Arne Andersson. Starting in 1942, they exchanged the mile world record a total of five times over three-year period, taking it from 4:06.1 to close to the four-minute barrier at 4:01.3.

Progression of the World Mile Record from 1923-1954

Girl running


Paavo Nurmi


23 August 1923



Jules Ladoumègue


4 October 1931



Jack Lovelock

New Zealand

15 July 1933

Princeton, N.J.


Glenn Cunningham

United States

16 June 1934

Princeton, N.J.


Sydney Wooderson

United Kingdom

28 August 1937

Motspur Park


Gunder Hägg


1 July 1942



Arne Andersson


10 July 1942



Gunder Hägg


4 September 1942



Arne Andersson


1 July 1943



Arne Andersson


18 July 1944



Gunder Hägg


17 July 1945



Roger Bannister

United Kingdom

6 May 1954


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