"I’m just off to do some Fartlek-training"

AS WELL as being the most ear-pricking word I’ve ever heard, the Swedish word “Fartlek”.

“Fartlek” - which means “speed-play” - is also a specific type of endurance-building athletic training, in which strenuous effort and normal effort alternate in a continuous exercise.

Here’s an example of Fartlek-training: