What Are Fartlek Runs? How Should You Use Them in Training?

If you’ve ever heard the term in passing and wondered what are Fartlek runs, it’s a form of running that can improve your speed. Specifically, Swedish term means “speed play,” which started an effective form of training that combines nonstop intervals of varied intensity. This training system was developed in the 1930s by Swedish trainer Gösta Holmér and gained popularity due to its capability to improve both aerobic and anaerobic fitness for runners. Fartlek runs offer a dynamic and engaging approach to training, giving runners the tools they need to improve upon their mile or 5k time, for example.

Benefits of Fartlek Runs 


4. Bettered cardiovascular fitness

By incorporating bursts of high-intensity training into your running routine, Fartlek runs help to improve your cardiovascular fitness. The variation in intensity challenges your heart and lungs, adding their capacity to deliver oxygen-rich blood to your working muscles. 

3. Increased anaerobic threshold

Fartlek runs can help raise your anaerobic threshold, which is the point at which your body switches from generally aerobic energy product to anaerobic metabolism. Training at intensities near your anaerobic threshold improves your body’s capability to clear lactate.

2. Enhanced internal durability and focus 

The ever-changing nature of Fartlek runs pushes you out of your comfort zone, helping to develop internal durability and improve your focus during grueling running situations. By embracing the unpredictability of Fartlek training, you come more equipped to handle races and overcome internal walls.  

1. Versatility and rigidity in training 

One of the major advantages of Fartlek runs is the flexibility it provides. You can fluently customize the duration, intensity, and structure of your Fartlek exercises to align with your specific training goals. Whether you are a new or educated runner aiming to increase your speed, Fartlek runs can be adjusted to suit your needs.

ALSO READ: How to Become a Runner 

How to Incorporate Fartlek Runs in Training 

Before incorporating Fartlek runs into your training routine, it’s essential to establish clear training goals. Determine how and when you want to increase your race pace, so that you can choose the proper Fartlek plan. Assess your current fitness position to insure that the intensity and duration of your Fartlek runs align with your capacities. As you add difficulty and volume to your exercises, you should do so gradually to avoid any injuries.

Another tip when starting Fartlek runs is to incorporate a dynamic warm up to prepare your muscles and joints. Some exercises that can help prepare you are leg swings, high knees, and lunges, which spark the major muscle groups and increase your range of motion. 

Establishing work and recovery intervals 

Determine the duration and intensity of your fast intervals grounded on your training goals and fitness assessment. For speed enhancement, shorter and further violent bursts are recommended, while longer intervals at a moderate pace can enhance endurance. Alternate the fast intervals with easy recovery jogs to allow for active recovery.  

Choosing a training route 

It is important to select a route that allows you to vary your pace. Specifically, running along a busy road or jogging path can make Fartlek style a bit more difficult because you will slow down and speed up on and off. It can be helpful to incorporate inclines, declines, and varied terrain to simulate race conditions and challenge different muscle groups.  

Monitoring intense situations 

Pay attention to your perceived exertion during each interval. Aim to maintain a comfortably hard pace during the fast intervals while allowing for acceptable recovery during the recovery stages. 

What Are Fartlek Runs and Example Workouts?

What Is a Fartlek Run? Benefits of Fartlek Training
Example from Shape

Basic Fartlek 

In basic Fartlek training, you start with a warm up for a few minutes before you start to alternate between fast intervals at a grueling pace and recovery jogs. Usually, you would select the same amount of time going fast as you would cooling down, so one minute on and one minute off. Repeat this pattern for 6 cycles. Finish with a cool down.  

Speed Play Fartlek Workout 

Begin with a few minutes of warming up. During your run, spontaneously vary your pace, speeding up and decelerating down. Incorporate milestones, similar as beacon posts or trees, to guide your pace changes. Maintain the advanced intensity sweats for 1- 2 minutes and recover for an equal or slightly longer duration. Finish with cool down.

Hill Fartlek Workout 

After a warm, find a hilly route in your neighborhood or at the gym. Alternate between uphill sprints and upwardly recovery jogs. Aim for shorter, violent uphill bursts and use the hills for active recovery, too. Repeat this cycle for 20-30 seconds for each interval and repeat at least 6 times. As always, be sure to cool down after.

Time-Grounded Fartlek 

After a few minutes of warming up, set your watch to interval timing, between 30-60 seconds. During this time, alternate between briskly-paced and recovery intervals. Your watch can alert you to when it is time to change paces. Once you’ve gotten to your desired running time whether that be 15-45 minutes, you can finish the intervals and end with a cool down.

ALSO READ: 10 Best Socks for Running

Tips for Effective Fartlek Training 

Tim Foster

To maximize the benefits of Fartlek runs and insure a safe and effective training experience, consider the following tips :

Listen to your body: Pay attention to any signs of fatigue or pain. Acclimate the intensity and duration of your intervals as a result to prevent overtraining and injuries.   

Gradually increase intensity and duration: To avoid unforeseen injuries, make sure to gradually increase your intervals whether that be your pace or the amount of time you increase speed.

Vary the terrain and environment: Explore different routes and training spots to keep your Fartlek runs engaging and stimulating. Running on different terrain similar as trails, hills, or tracks can target different muscle groups and add variety to your exercises.  

Incorporate rest and recovery days: Allow your body time to rest and recover between Fartlek sessions. Acceptable rest promotes muscle form and growth, reducing the threat of overuse injuries. Schedule recovery days or light exercises to balance the intensity of your training.  

Track and estimate progress: Keep a training log to cover your Fartlek exercises and track your progress. Record important details similar as distance covered, intervals performed, and perceived exertion situations. Regularly assess your performance and make adaptations to your training plan as needed.

Common Mistakes to Avoid

To ensure optimal results and minimize injuries, avoid these common mistakes when incorporating Fartlek runs into your training routine:  

Overtraining or shy recovery: Pushing yourself too hard without allowing sufficient time for recovery can lead to fatigue, collapse, and increased threat of injuries. Balance your Fartlek runs with rest days and lighter training sessions. These runs are not meant to be done every day or even too many times in one week.

Neglecting proper warm up and cool down: Skipping warm up exercises and cool down jogs increases the risk of muscle strains and injuries. Prioritize a dynamic warm up routine before each Fartlek session and allow time for a gradational cool down at the end.  

Failing to vary pace: Fartlek runs are about embracing variation in pace and intensity. Avoid constantly running at the same intensity throughout your entire run, or else you won’t see the same kind of speed results that Fartlek encourages. Mix up your speed to target different energy systems and improve your overall performance.  


What’s the difference between Fartlek runs and interval training? 

Fartlek runs are more flexible and unshaped compared to traditional interval training. While interval training involves specific timed or measured intervals, Fartlek runs allow for naturalness and variation in pace.  

Can newcomers incorporate Fartlek runs into their training routine? 

Yes, newcomers can gradationally introduce Fartlek runs into their training routine. Start with shorter intervals and lower intensities, gradually adding to the challenge as your fitness improves.  

How frequently should I include Fartlek runs in my training plan? 

The frequence of Fartlek runs depends on individual pretensions and overall training volume. It’s recommended to include Fartlek sessions once or twice a week, while also incorporating other forms of training for a well-rounded approach.  

Can Fartlek runs help with weight loss? 

Fartlek runs can be an effective element of a weight loss program as they help burn calories and improve cardiovascular fitness. Still, you should combine Fartlek runs with a balanced diet and other exercises to see the best results.


So, what are Fartlek runs? Now, you know that this kind of training offers a dynamic and effective training system for runners of all experience levels. By incorporating bursts of speed and varied intensity into your mileage, you can improve your mental and physical running health and customize your training to what works best for you. Be sure to listen to your body and track your progress for optimal results.  

CHECK OUT: The Best Brooks Running Shoes for Females