What is a Fartlek run? How do you do it?

Fartlek is like unstructured interval training. You make it up as you go. You do what you feel like you need/want to. It likely shouldn't be a VO2max workout, but could be a great tempo workout. You can make it hard, medium, long, easy. It's speed play, it should be fun.

There are two types of fartleks

1.) original Swedish speed-play ran on natural surfaces like dirt, grass or sand in a natural setting and at least forty minutes in duration and you pick an object in the distance and run hard to it then jog, walk or run until you have enough energy to repeat with another distance and pace made up on the spot, repeat several times until you are tired but not spent

2.) modern fartlek can be done on a track or road and is usually something like, warm up, 1 min on, one min off, 2 min on 2 min off and repeat or whatever structured interval session you want. Note: this is not a true fartlek, I have no idea why runners accept this as a fartlek

Runner of fartleks wrote:

There are two types of fartleks

1.) original Swedish speed-play ran on natural surfaces like dirt, grass or sand in a natural setting and at least forty minutes in duration and you pick an object in the distance and run hard to it then jog, walk or run until you have enough energy to repeat with another distance and pace made up on the spot, repeat several times until you are tired but not spent

2.) modern fartlek can be done on a track or road and is usually something like, warm up, 1 min on, one min off, 2 min on 2 min off and repeat or whatever structured interval session you want. Note: this is not a true fartlek, I have no idea why runners accept this as a fartlek

Per #2 above, anything that is (a) structured and (b) on the track is not fartlek, so you are correct in this analysis.

The best type of fartlek on the track is the "coach's perogative" wherein the runners have no idea in advance what the interval lengths will be. Usually the coach blows a whisltle to indicate when it's time to run hard and when to let off - can be time-based intervals, position on track intervals, point-of emphasis intervals, etc.

But the point is to prepare the runners for the unexpected/unknown that most often occurs during races, preparing them to think on their feet and make the necessary mid-race adjustments.

'Runner of fartleks'. Above, has defined it as well as could be. I ran a lot in the 70s and definition 1 was what everyone meant by the term then. I also will point out that I do know anyone who realy did this regularly. I might have like twice in all of HS (I was not on an official school team and therfore worked out as I saw fit).

Fast forward several decades and it's now a popular thing. Or at least a popular term, since one could easily argue that definition 2, which is what everyone does now (but usually not on a track, in my impression) is not really fartlek.

I think for you, looking at mid distances, the most useful way to integrate this concept is the long run with accelerations or surges throughout. If you going really long you may not be psyched on this but a run of an hour or hour and a half can be done as follows:

First 15 min WU

Accelerate to something around race pace and hold it for several seconds.

Cruise another 5 min.

Accelerate again. These can get gradually faster and/or longer, but if they're more than 30 second. It becomes a different type of workout. Also, they probably shouldn't really get to 100 percent full speed, just approach it but don't squeeze out that last couple percent.

Do a dozen surges total. Maybe more or less.

Last 15 CD

I recently did the following:

3 min hard. 1 min easy.

Do this 10X

2 min hard. 1 min easy

Do this 10X

1 min hard. 1 min easy

Do this 10X

The 2 mins were slightly faster than the 3s and the 1s a little faster yet. The minutes 'off' got slower but really shouldn't. The idea is that you still cruise but don't really jog. This was on road with no mile markers. Just by feel. Great workout; 90 mins, 60 hard. However, this is probably better if you're training for something like 15k or longer. Not as much of a 1500 type workout, but who's to say some of these 15/5k guys don't do this kind of thing? I know marathoners do.

Hope something in here is informative and helpful. Good luck!l

I prefer hill fartleks. I run a rolling course and run hard either up or down the hills. The speed will depend on the size of the hill. That is more random than a 1on/1 off or set distances. You can monitor your effort as you go.

Runs with pickups are another idea, and you probably shouldn't mix them with the idea of farleks. Anyone you meet today who talks of fartleks has a very specific idea, which is not spontaneous pickups.

I like to think of the purpose of fartleks as a bridge to interval work from base fitness. You're probably not ready to hammer useful track sessions just off your base. But you could certainly do analogous workouts in the "modern fartlek" style mentioned above.

Runner of fartleks wrote:

Note: this is not a true fartlek, I have no idea why runners accept this as a fartlek

Is American English not true English, either? Just leave it. This is what people say now.

Runs with intervals of predefined time allotments are not playful. That's a regular old Swedish fart. Why, it's only speed-work!