Do any serious runners actually do Fartlek runs?

Perhaps your Swedish is good, but your English is bad.In my Swedish-English dictionary:fart: verve, pep, impetus, pace, speed, zingsnabbhet: fastness, celerity, swiftness In the English language, "velocity" is "speed" with a direction, i.e. "speed" is the scalar magnitude component of the equivalent vector quantity "velocity".In fartlek, the direction is irrelevant or otherwise never specified. The training emphasis is never on changing your direction in unpredictable, random or chaotic ways, but rather on the unplanned variation of pace (intensity or effort), and duration.Therefore, "speed-play" looks like a much better translation of the Swedish word "fartlek" into English, with respect to the training concept. In any case, it sounds better than "velocity-play".

LR Swedish teacher wrote:

Your translation of fartlek is incorrect. The Swedish word "fart" means velocity. The Swedish word for "speed" is "snabbhet".

I do 10-13 miles of it once or twice a week throughout winter. Completely random, anything from 150m hill to about a mile and cruising along at around 6min mile pace in between.

English teacher wrote:

Perhaps your Swedish is good, but your English is bad.

In my Swedish-English dictionary:

fart: verve, pep, impetus, pace, speed, zing

snabbhet: fastness, celerity, swiftness

In the English language, "velocity" is "speed" with a direction, i.e. "speed" is the scalar magnitude component of the equivalent vector quantity "velocity".

In fartlek, the direction is irrelevant or otherwise never specified. The training emphasis is never on changing your direction in unpredictable, random or chaotic ways, but rather on the unplanned variation of pace (intensity or effort), and duration.

Therefore, "speed-play" looks like a much better translation of the Swedish word "fartlek" into English, with respect to the training concept. In any case, it sounds better than "velocity-play".

LR Swedish teacher wrote:

Your translation of fartlek is incorrect. The Swedish word "fart" means velocity. The Swedish word for "speed" is "snabbhet".

When runners talk about "speed training" they generally mean fast running (obviously) but the Swedish word "fartlek" stands for a running session where you change pace repeatedly during the run, and you don´t necessarily have to run fast anytime during the run (Lydiard talked about how easy fartlek could be beneficial), so the translation "speed-play" is somewhat misleading. Of course, a fartlek run could be hard as hell, but that´s a different story.

Of course "play" means play, like having fun. "Speed training" sounds like "speed-work". I think it has both physical and mental benefits.

LR Swedish teacher wrote:

When runners talk about "speed training" they generally mean fast running (obviously) but the Swedish word "fartlek" stands for a running session where you change pace repeatedly during the run, and you don´t necessarily have to run fast anytime during the run (Lydiard talked about how easy fartlek could be beneficial), so the translation "speed-play" is somewhat misleading. Of course, a fartlek run could be hard as hell, but that´s a different story.