Fartlek training was first practiced in Sweden in the 1930s, with its literal translation being speedplay. In a fartlek session, typically, the athlete will vary the speed at which they are moving at different stages of a run for set periods of time with faster, slower and sometimes intermediate speed runs. Generally the variables that are time based, with distance being a secondary concern (expect perhaps the total distance to be covered).

Why Should I do Fartlek Training?

Run at Speed for Longer

This will sound technical, but is relatively simple, so read on! Fartlek training allows you to increase you speed over sustained periods of running, by increasing your lactic threshold level (the point at which your body starts producing significant levels of lactic acid due to anaerobic respiration).

This is because of the combined factors of your body learning to run more efficiently at a certain heart rate (hence it is lower at the same speed), and also, to a smaller extent, increasing the heart rate at which lactic acid is produced. There is also a element of your body coping better with lactic acid in its system and processing it better.

To run at your best in long distance races you are constantly trying to run at around your lactic acid threshold level - any faster and you won't last the race, any slower and you won't perform to your best.

Double Benefits

Scientifically fartlek training also has the benefit that, as a bi-product, lactic acid produces lactate. This is an energy source and is used by the body in the slower periods of running, thus allowing the body to re-use the energy is has stored. This is called the lactate shuttle.

This means that there is a dual benefit to fartlek training, the athlete gets to use the energy which is a by-product (lactate) and therefore can run for longer than might have been expected as they are not using the normal energy source all the time. And, there is the development of the athletes ability to run with high levels of lactic acid in their system.

Generally it is good to do these sessions in an off-road / track environment eg a park, as it is less stress on the legs and there is no requirement in the session to do particular distance in specified times.

What should I do?

Setting specific fartlek sessions is tough, as by it's nature the athletes should "play" with their speed. However, a typical fartlek might be to do a 5 mile run at a steady aerobic pace and within that do 8 or so efforts, of one or two minutes each, faster which will be far more anaerobic. The speeds of the two sorts of running would depend on the individual, but it is important that there is a distinct difference in the two paces.

In order to use the benefits of the lactate shuttle, it is sometimes worth making the initial efforts slightly faster than you anticipate being able to do throughout the fartlek session, or slightly longer in order to bring the levels of lactic acid up near the start of the session. Also, the slower phases shouldn't be more than 2-3 minutes in length, as this is how long the lactate will be available to you as an energy source.

Fartlek Intensity

A fartlek session can be of any intensity you like, so is useful to give to an athlete used to target times in each session as they will adapt it to how they are feeling on the day. Make sure, as a coach, that you know you athletes, however, as this may lead to some working too hard or not hard enough - try to structure the session accordingly.

In a group of athletes (generally aim for them to be of a similar standard) it often gives the athletes even more freedom if you let them (in rotation maybe) control the length of each of the efforts.

Fartlek Progression

An athlete will be able to gradually improve their fartlek sessions over time by increasing any of the variables (distance, either of the paces, or the length of harder effort). There is no reason why three different paces should not be included.

This kind of session is often more fun than a steady run and can help an athlete psychologically break up a routine, if they feel they are stuck in a rut. As well as being fun it is a relatively easy session mentally since there are no strict targets to worry about.

Fartlek Training Systems

We believe you can develop your own fartlek training methods using the guidelines above and how they feel for you. If you wish to find out more about fartlek running, that has been used by coaches and physiologists in the past you can look into methods from Astrand, Christensen, Saltin, Hedman, Gershler and Watson amongst others.

If this all seems a bit daunting, we can put together a schedule prepared specifically for you from our team of experienced coaches with our Online Coaching.

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