Fartlek Runs (or Fartleks) for Speed and Endurance


Fartleks may be the worst sounding, but one of the most important foundational workouts for runners. Swedish for “Speed Play”, Fartleks focus on continuous running and interval training in the same run whereas tempo running is continuous and track intervals focus on speed. It is literally the best of both worlds, as the workout varies between “on” where you are moving at a fast pace before going “off” into a comfortable pace without stopping to rest.

Why Run Fartleks

From a physical standpoint, Fartleks target speed and endurance. During the “on” phase of the workout you are moving at a fast pace for any distance you want to target, with a focus on speed. Since this run is done on the open roads (or even while running trails), you will likely be in speed mode for a set period of time versus knowing how far the distance is for a repeat. While you can use a GPS watch to calculate distance, for example running 400 meters in the “on” portion, running at speed for a full minute is just as effective.


Fartleks build endurance as this is a continuous running workout. During the “off” phase of Fartlek, your goal is to downshift into a jog, or for more advanced runners 75% of the pace you just completed, before ramping back into the next speed burst. This allows your body to get attuned to the pace variations that happen during a race while having a strong endurance workout since you never stop running.

Running Control

From a mental and physical aspect, Fartleks greatly assist with pace control and being able to respond with confidence to a race surge or struggling to get back into your pace after a tough hill or mile. They also give you clarity and intimacy into what your body is capable of managing from a pace perspective without feeling like you are out of your league. This is achieved by the sense of pace gained while moving on and off. If you know what is “fast” per your body, you will easily know if the pace you are trying to maintain is too fast or for how long you can maintain a fast pace in a race scenario.

Never a Boring Run

Beyond race day, Farteks are a great way to break up the monotony of running if you feel stuck in a rut. You can run Fartleks anywhere, choosing to be highly structured with a GPS watch for distance, running between objects, for a set amount of time per repeat… or more unstructured by randomly speeding up for varying distances. They key to Fartlek running is to mix it up, challenge yourself, but enjoy the flexibility offered by this ever changing training session.

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I have been a lifelong fitness student and enthusiast ever since winning the gold at conference in the 100 butterfly and 200 IM back in my “glory days.” I am also a writer and the marketing wizard here at My Top Fitness. I have an ever-growing list of interests, including swimming, running, golf, bowling, speedcubing, speed running (old Nintendo games), locksport, cooking, chess, tournament poker, fishing, hiking, camping, and sleight of hand, just to name a few. On some platforms, you can find me as the self-appointed “Jack of all Hobbies” I am a proud husband and father of 2 children, a.k.a. gremlins, and I am super excited to help as many people as possible on their individual fitness journeys.