I was out for my running workout today. And part of my workout was to do a fartlek.
Nope. I did not fart while I was doing it! haha!
But what is Fartlek by the way?
Fartlek, which means "speed play" in Swedish is a form of interval training that can be effective in improving your speed and endurance. Fartlek running involves varying your pace throughout your run, alternating between fast run and slow jogs. It differs from traditional interval training in that it is unstructured; intensity and/or speed can be varied and work-rest intervals can be based on how the body feels.
Most fartlek sessions last a minimum of 45 minutes and can vary from aerobic walking to anaerobic sprinting. Fartlek training is generally associated with running, but can include almost any kind of exercise.
Here is an example of a Fartlek Session that I have read in Runner's World:
In your city, neighborhood, or office park, use blocks as your "track." You can go around the block or do an out-and-back. Start at a slow pace for five to 10 steps, then gradually increase the pace for 20 to 50 steps, then run at race pace (but not all out) for one full block. Start with two or three fartlek segments and build to six. Walk for one or two minutes between each faster section.
Pick a telephone pole, mailbox, stop sign, or anything up ahead and run to it. You can choose one item (all telephone poles, for example) or multiple landmarks to create varying lengths of speed segments. On each segment, gradually pick up the pace until you're running fast but not all out. For the last 20 steps, hold the pace, but focus on relaxing your body and allowing momentum to take over. Walk or jog for half the distance of your repeat, then spot your next landmark and take off again. Continue for a total of 10 to 15 minutes, before running an easy five to 10 minutes to cool down.
Fartlek training puts a little extra stress on your system, eventually leading to faster speeds and improving your anaerobic threshold.