Plus Two Sample Fartleks Workouts

By Marnie Kunz, CPT

Fartleks are a form of speed workout that can make you a faster, stronger runner. Whether you’re a beginning runner or are training for a marathon, fartleks can help you improve your running efficiency and pace. You may be wondering what are fartleks and how can they help me? Well, you've come to the right place! As a running coach and longtime runner, I’ve used fartleks many times over the years to help people get faster. I’ll go over what fartleks are, how they can help you, and how to add fartleks to your running program.

What Are Fartleks?

Fartleks is Swedish for “speed play.” Fartleks are runs where you go at a relaxed pace and mix in bursts of speed throughout the run. Fartleks can be as formal or informal as you'd like. When I was in school running cross country, we learned to do fartleks informally when our coach would pick something like a pole in the distance and tell us to speed up and run fast to the pole, then return to our regular pace.

You can also do fartleks in a more measured manner, by running fast for a specific time or distance at periodic intervals during a regular paced run. You might run for 4 minutes at a relaxed pace, for instance, and then run fast for 1 minute and repeat. Between the speed bursts, you will want to run at your regular base run pace, which should feel comfortable. (Here are more tips on how to do base runs).

Benefits of Fartlek Workouts

There are many benefits of fartleks. Below are some of the advantages of doing fartlek speed workouts:

Better running form

Fartleks train your body to run more efficiently even while fatigued. Because you run continuously, fartleks are a great simulation for racing, as you will have times you need to speed up during a race.

Faster running speed

Fartleks will improve your running pace. In races, you will be able to run faster and also will be better equipped to do surges and pass people during the race.

Improved endurance

Research shows that fartleks workouts boost your endurance and train your body to go fast even when fatigued. Unlike interval workouts, fartleks require you to run continuously at your regular running pace between speed bursts, which improves your endurance.

Adaptable for all fitness levels

Fartleks are an excellent adaptable workout with beginner-friendly options as well as ways to make them more advanced. If you are a beginning runner or training for your first 5K, for instance, you can do just a few short bursts of speed during a 2-mile run. For runners training for longer races or who are more advanced, a fartlek workout may be longer, such as 7 miles long with 12 bursts of speed.

Increases VO2 max

VO2 max is a measurement of how much oxygen your body is able to use during exercise. When you improve your aerobic fitness level with workouts such as fartleks, you improve your VO2 max, which basically means your body becomes more efficient at using oxygen when you run, and you’re able to run longer and faster.

How to Do Fartleks

You can do fartleks with an informal system or a more measure approach. For informal fartlek training, turn a base run into a fartleks workout by running at your regular pace. Then periodically pick out an item in the distance and run fast toward it. For the speed bursts, run at 80% to 90% effort level and go for about 100 meters (equal to the straight length of a running track) or more.

If you are just getting started with fartleks, a more measured approach may be easier to get the hang of the speed workout. I have included a sample beginners fartleks workout here:

Run 800 meters (2 laps on an outdoor track or half of a mile) at a relaxed pace to warm up. Do dynamic stretches.
Run 400 meters (one lap or .25 of a mile) at a relaxed, base run pace.
Run 100 meters (one straight side of a track or .062 of a mile) at 90% effort level.
Repeat to do 3 fast runs and 3 regular paced runs.
Cool down by running 800 meters slowly. Stretch.

Total Run Distance: 2.19 Miles

You can adapt this workout to a more advanced running level by adding more speed intervals (followed by regular paced running) for a longer fartlek run.

And here is an advanced fartleks workout for a longer distance run, using time instead of distance as a measure:

Run 10 minutes at a slow, relaxed pace to warm up. Do dynamic stretches.
Run 1 minute fast (at 90% effort level).
Run 3 minutes at your regular base run pace.
Repeat to do 8 fast intervals and 8 relaxed recovery runs.
Run for 6 minutes at a slow pace to cool down. Stretch.

Total Run Time: 48 Minutes

If you need some suggestions for dynamic stretches to warm up, check out my post on dynamic stretches. Dynamic stretches involve movement and help your body warm up for the workout ahead.

Fartleks Pace

When you run fartleks, you should aim for an 80% to 90% effort level for your bursts of speed. This will feel like a challenging, fast pace that you would not be able to keep up for long yet it won’t be an all-out sprint and you will be able to maintain this pace for your short fartlek bursts.

With fartleks training, you do not need to be worried about the exact pace and time, unlike interval training. Going based on your perceived effort, your fast pace for fartleks should be 8 or 9 out of 10 on the perceived exertion scale. And your running pace between speed bursts should be your regular base run pace, a pace at which you could comfortably keep up a conversation.

Fartleks vs. Interval Training

If you are wondering what is the difference between fartleks and interval training, that is a good question. In interval training, you have a slower recovery pace or even rest between speed intervals, whereas fartleks have a more steady, regular base run pace between speed bursts. In addition, fartleks are more informal in nature and you do not need to measure your exact pace for each speed burst. With interval training, it’s important to keep a record of your speed intervals and aim for the exact same time or pace for intervals of the same distance.

For more on interval training, check out my post on Interval Training for Beginners.

When to Do Fartleks

If you are just getting started with speed workouts, I recommend doing fartleks once a week to start building your speed. If you are already doing other speed workouts, add one fartleks workout a week to your training. When you do fartleks or any speed workout, follow it with a recovery day, rest day, or easy training day. You do not want to do two days of speed workouts or hard runs in a row. (Long runs, races, and speed workouts count as hard runs).

Overall, I recommend doing speed workouts at least once a week and at most three times a week to improve your running speed, form, and endurance. Follow the principle of progressive overload and gradually add more intensity or duration to your speed workouts as you progress over the weeks.

If you need a customized running training plan, you can order one in our Training Center and I will create a training program just for you so you can crush your running goals.

I hope these sample fartleks workouts help you on your running journey. Have you tried fartleks workouts? What did you think? Happy running to you!😊

Marnie Kunz is a NASM-certified trainer and USATF- and RRCA-certified running coach, Brooklyn resident, Akita mom, and the founder of Runstreet.

Fartleks Workouts to Help You Run Faster