TRAINING: Playing with Fartlek

I had a conundrum on Thursday: I wanted to get my scheduled fartlek session in without harming my freshness for Saturday’s race too much.

To this end I came up with the following session which I felt would be valuable in “checking all my gears” and working some speed without tiring me out too much.


I had decided I wanted to do Fartlek for about an hour, which would most likely be around 12km or a bit more.


As I didn’t want to sprint all out all the time and didn’t want a longer recovery between sprints than 1:30, I settled for an easy to remember 30 seconds on/1:30 off or 30 repeats during the 1 hour.

This left me with an idea: I’ve got 5 main race paces (half-marathon, 10k, 5k, 3000m and 1 Mile) that I use regularly. 30 divided by 5 is six. So I would do 5 times 30 seconds at first half-marathon pace, then 10k pace all the way down to 1 mile pace and then restart. Between each effort there was the 1:30 float.


I used a stretch of 1.5k flattish road away from my house and back, meaning I expected to go back and forth about 4 times. There was both small uphill and small downhill bits which affected the tempo of each repeat somewhat, but that was fine, after all it was a fartlek not a set interval session. And running different speeds (efforts really) on different gradients added to the challenge of the session.


Pleasantly surprised, time flew and I felt I got a good workout and learned a lot about the differences between the paces I employed (e.g. high knee lift motion only seems to start at 10k pace, legs only feel like moving really fast at 3000m and 1 mile pace and so on) and I didn’t get excessively fatigued.

As a transition session aimed at keeping the legs fast but reasonably fresh I think this was a success and a keeper for the future.


While there were variations on average for each of the 6 cycles I got faster from first rep to fifth rep as planned. The average pace for a session like this turned out to be 4:41min/km (12.4km for the hour) despite the slow 1:30 recoveries (which weren’t super-slow in any case as you are not completely destroyed by the efforts).


Closer to the season, you can opt for faster speeds all-round or random efforts. A more undulating course will also make it even more like a hill race. In terms of pace judgement and adapting to random effort vs. terrain demands, this session has a lot to teach.