Using Fartlek Workouts for Maximising Your Running Performance

Once your initial training routine has been established and you’ve spent sufficient time working on your base-level fitness, you can start thinking about improving your performance by getting the most from your available time.

It’s still advisable to keep most of your training at an easy aerobic pace because although the addition of faster-paced running will improve your fitness quicker, it will also increase your risk of injury – unless you keep it controlled.

According to Run in the Dark coach and international endurance athlete John O’Regan adding just one faster-paced session per week will pay dividends regardless of your fitness level. Still, it needs to be controlled and only do what you are able for.

For a beginner wanting to improve, you can consider anything that has you breathing harder than usual to be speed work. This pace only needs to be faster than your regular training pace to be of benefit.

Try Adding Elevation

Before you consider adding faster-paced sessions to your weekly routine, try running routes that include some hills, as this will increase leg strength and also work the heart and lungs because of the increased effort required. Stronger legs will be better prepared to handle faster running, which helps with staying injury-free.

Another option, and one of John O’Regan’s favourite sessions to help improve fitness through speed work without overdoing it is the Fartlek Session which comes from the Swedish word for Speed Play.

What is a Fartlek Training Session?

A Fartlek Session is basically an unstructured session made up of primarily easy running with some shorter / faster elements added in, and you do as much or as little as you feel able for.

An example Fartlek session would be 10 minutes of easy running followed by a short sprint for as long as you feel comfortable and then slowing down for as long as it takes to recover before going again.

You could pick landmarks or objects on your route, such as lampposts, and use the gap between the first two for a sprint and recover to the next, and so on. As always, ensure to warm up sufficiently and allow time to cool down – warm-ups are even more essential before a fast-paced session.

This session will feel like hard work, but the payback will come on your regular running days as they will feel easier and more enjoyable.

How to Use Fartlek to Improve

For continuous improvement you need to:

  • Be consistent with your training
  • Build up slowly and be patient with progress
  • Include rest days
  • Follow hard days with easy or rest days
  • Warm-up and cool-down
  • Vary your running route and don’t avoid hills
  • Run on different surfaces
  • Only do what you can recover from
  • Pay attention to staying injury free, as you can’t train if injured, and you won’t improve if you don’t train

It’s advisable to consult with your doctor before starting on any new exercise regime if starting from a base of zero fitness and years of inactivity or returning from illness or injury.


About John O’Regan

John O’Regan is the official running coach for Run in the Dark. 

John has run over 50 marathons and ultra-marathons on seven continents / 20 countries and represented Ireland on ten occasions at ultra-marathon distance. Follow him on Instagram  and Twitter at @johnoregan777. 


Run in the Dark

As darkness sweeps around the globe every November, 25,000 people worldwide get up from their armchairs, slip on their red flashing armbands and pull on their running shoes to complete a 5k or 10k. From Sydney to San Francisco, together, we run for those who dream to walk.

Sign up to Run in the Dark from June each year, or join the waitlist, and we’ll let you know when registration opens.