The Running Channel's Half Marathon Fartlek
Running, September 11, 2025
Including a range of running intensity into your training is a great way to build your fitness by boosting your top end speed and also developing your ability to hold a sustained intensity within a single workout. This workout is great for athletes running a 10km or a half marathon, whether as a stand alone event or as part of an Olympic distance triathlon or an Ironman 70.3.
Fartlek is a Swedish term that is often used by runners and it means speed-play. See a previous post about training intensity (levels) to know how hard to work.
The inspiration for this workout comes from a video on the Running Channel:
The Running Channel's Half Marathon Fartlek
- 10min WU Level II;
- 4km Level III-;
- 3km Level III+;
- 2km Level IV;
- 1km Level V;
- 10min CD Level II;
- 10min Stretching
The Warm Up (WU) should be done at an intensity that is steady but not over consuming at Level II for ten minutes.
The main set is made up of four reps. Each rep gets progressively faster, but conversely shorter in distance.
Start with running for four kilometres at marathon pace (Level III-), then increase to half marathon pace (Level III+) for three kilometres. There is no rest between reps. The third rep is two kilometres long and is run at 10km pace (Level IV) and then conclude with one kilometre at Level V.
The Cool Down (CD) is at low-intensity jogging (Level II) for a minimum of ten minutes.
Finish with 10 minutes of stretching to assist with the recovery.
If you would like further advice feel free to contact me.
I am the Head Coach & Director of Qwik Kiwi – Endurance Sports Consultant.
I specialise in assisting first-timers and recreational athletes to achieve their sporting goals. I can be contacted at coachray@coachray.nz and 021 348 729.
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