fartlek

American  

[fahrt-lek] / ˈfɑrt lɛk /

noun

1. a training technique, used especially among runners, consisting of bursts of intense effort loosely alternating with less strenuous activity.

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fartlek British  

/ ˈfɑːtlɛk /

noun

1. sport another name for interval training

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Etymology

Origin of fartlek

1950–55; < Swedish fart speed + lek play

Example Sentences

This simple approach is a classic form of fartlek training.

From Science Daily • Oct. 20, 2025

Swedish for “speed play,” fartlek workouts use a type of interval training that involves a series of high-intensity bursts with recovery periods between them.

From Seattle Times • Oct. 4, 2022

No need to check your heart rate or track each interval’s length, in time or distance, said Dr. Wisloff, who also trains with fartlek.

From New York Times • Nov. 10, 2021

In other words, you have to do a lot of sprinting – even if, like me, you hate it – or mix it with slower running in what’s known as fartlek.

From The Guardian • Jan. 1, 2019

Even though we felt as if our hearts were in our throats, Neile and I enjoyed our fartlek workout so much we thought we might try it again the next morning.

From Washington Post • Aug. 31, 2015