Why is everybody obsessed with Fartlek training? We speak to Sam Wood about the fitness trend.

If you live and breathe the fitness industry you no doubt would be very familiar with Fartlek training.

If not, then let us (actually, let Sam Wood) explain the fitness technique that is not exactly new but is now creating a lot of buzz in the fitness world.

Oh and don’t worry, despite it’s name, this has nothing to do with flatulence…

When you Google the term, the first thing that comes up is that fartlek is the Swedish term for “speed play”, which doesn’t really tell you much.

But it is basically a form of interval and speed training that consists of a random change of pace in your exercise – be that running, swimming, rowing or cycling.

We spoke to Sam Wood, fitness entrepreneur and creator of 28 by Sam Wood, so that he could break it down for us.

What exactly is Fartlek training?

“It is interval training with randomised intervals,” the former Bachelor explained

“So rather than a set time of, you know, 30 seconds on, 90 seconds off, fartlek could be push for a minute, then rest for a minute, then a ten second sprint, then a hill. It’s completely randomised to not let the body predict what is going on.”

Sounds like interval training, right?

It is certainly similar, but fartlek training is much more arbitrary; not pre-determined by any pattern or plan. Essentially the idea is that (if you were running, for example) you can alternate between sprinting, jogging, walking and all other paces at your own preference.


You still need to be disciplined, but it is much more flexible than interval training, allowing you to exercise at your own fitness level as you decide.

There are usually no timers and there is much more variation.

Why is Fartlek effective?

“It gets your heart rate out of that steady state zone, so that’s going to be good for accelerating your metabolism, it’s going to be good for forcing you out of your comfort zone and it’s going to make you run faster” Wood said.

By doing short sharp efforts whilst exercising, you are increasing your metabolism long after the exercise finishes, the fitness expert explained.

“If I go for a jog for half an hour, is that good for me? Absolutely. But my metabolism will come back down to resting pretty quickly. But if I go for an explosive fartlek session…my metabolism will be elevated for hours after I finish that workout”.

Wood also shared that whilst general jogging is good for endurance, fartlek training is best if you’re wanting to increase your speed as well as stamina.

“If you don’t do any kind of speed training, you don’t typically get faster. Your endurance will build up and you’ll be able to plod along all day, but people need to do some sort of interval or fartlek training.”

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How do you do Fartlek training?

Fartlek is extremely easy to employ in your exercise regime and often needs no pre-planning.

Landmarks such as street lights, a specific building or post boxes could be used if you are running outside to give you some extra motivation to push yourself, but again, this is self-determined and adaptable to how your feeling.

“If you let the geography and surroundings dictate your fartlek training then that’s a really nice way of losing control but having some structure”


Wood mentioned that it is also particularly good if you’re training with a running group outdoors. Alternatively, if in the gym, it is easy to employ this technique on the treadmill, cycling bike and erg machine.

“You can absolutely do a fartlek session on a treadmill. A lot of the treadmills have the pre-programmed option…they’re randomised. It might give you a hill, it might give you a sprint. You just obviously need to be a bit careful that it’s still working within your capabilities”.

Who is Fartlek best for?

“If you’re a runner, who is having trouble breaking the 20-minute barrier for your 4km run, fartlek training would be a great way for you to increase both your speed and your endurance if you mix into your training maybe once or twice a week, rather than just your normal run” explained the fitness expert.

And as for if there is anything to be cautious of with Fartlek?

Wood mentioned that you should be careful of the impact it will have on your body if you do too much, too soon.

“Listen to your body, give yourself recovery, then go again. Don’t try to do too much too quickly. I think these people that decide they’re going to be a runner and then do six sessions in their first week, and can hardly walk, are the people that tend to get injured. So just progressively build up your workload”.