We’re continuing our weekly workout series with a fartlek run that will help you prepare for longer distances like a 10K or half marathon. Short and fast fartlek runs are ideal for preparing for the fast-from-start-to-finish 5K. However, in order to venture into the territory of 10K and half marathon training, you will benefit from changing the type of speed work you do. You could add more repeats or, even better, extend the length of the repeats.

Most runners can hold a fast pace for a few hundred meters, but many slow down when it comes to holding a hard effort for a few miles. In order to sustain a hard effort in a 10K or half marathon, you need to train differently than you would for a 5K – which means working on both your endurance and your speed.

Extending the length of the repeats will improve your endurance and ability to hold a hard effort for a longer amount of time. These intervals may seem intimidating at first, but if you are able to do shorter intervals, you are able to do these. Take this run one interval at a time.

Depending on your pace, 5 minutes will cover anywhere to ½ mile to just shy of 1 mile. That’s why fartleks are so beneficial for runners – they allow you to adapt your speed training to your abilities, so that you are training hard enough without wearing your body completely down. The workout prescribes 4-5 intervals: base how many repeats you do off of your current fitness level and overall weekly mileage.

In terms of effort, aim for what feels like an an 8 out of 10. This should be a hard effort and you should be only able to speak a word or two at a time, but do not sprint these intervals. You want to avoid slowing down if possible in the final interval. You should run the recovery intervals slow enough that your breathing steadies before the next interval. If you are training for a 10K, these intervals should be done at your goal pace or even slightly faster. For a half marathon, focus on running these 20-30 seconds per mile faster than your goal race pace.

The Workout:

  • Warm up with 10-15 minutes of running at an easy, comfortable pace.
  • Run 4-5 x 5 minutes at a 8-10K pace with 3 minutes of very easy running in between.
  • Cool down with 5-15 minutes of very easy running.

Ready to run? Click here for the full workout with helpful audio cues.