Fartlek 

Fartlek, (Swedish: “Speed Play”), approach to distance-running training involving variations of pace from walking to sprinting aimed at eliminating boredom and enhancing the psychological aspects of conditioning.
In simple terms, starting as a jog , slowly increasing your speed and ending it as speed run.

This treadmill workout is a fartlek workout that will not only help improve your speed, but also help prevent boredom on the treadmill.

Fartlek by YourUrbanPerson March 4, 2022

fartlek 

From the German translation 'Speed Play', fartlek is a training exercise used by distance runners to increase their anaroebic capacity. This increases racing performance greatly by allowing muscles to better cope with the lack of oxygen associated with high-intensity activities. The process involves speeding up to race pace for several minutes, then jogging for several minutes, repeating until workout is over.

Uli did 2 hours of fartleks yesterday to get ready for the Seattle Marathon, he's insane!

fartlek by Leif June 10, 2006

Fartlek 

An activity runners do when they change between sprinting and jogging

"Guy 1: Dude why did you slow down?"

"Guy 2: Just gotta do a Fartlek"

Fartlek by Chris3103 April 23, 2023

Fartlek 

Forced usage of alternating speeds and positions due to movements of ecstacy in cunnilingus, making it difficult to achieve maximum clitoral stimulation. In extreme cases, can result in having to start again, causing irritation to both sexes.

"She started moving her hips up, so I had to fartlek her. She hit me as she was 'so close', bringing shame upon my family name."

Fartlek by Rory McMoose April 27, 2005

fartlek 

newer slur used for a british person

you fartlek

he’s such a fartlek

fartlek by sirbuttlicker September 3, 2025

stoplight fartlek 

A form of cross-country training originally from Sweden, but adapted to a city environment. Like traditional backcountry fartlek, stoplight fartlek involves changing the tempo of the run, except instead of instinctually changing pace, the speed is governed by traffic and lights.

"I thought I'd take a leisurely jog around the park, but it turned into a stoplight fartlek when I tried to ride a greenwave and dodge a couple buses."

stoplight fartlek by Harris Bergstein August 8, 2008

Fartleberry

Although usually meaning a small piece of excrement attached to the hairs of your arse, sometimes known as a Clingon, it can also mean someone who is a minor, smelly, unpleasant nuisance that is sometimes difficult to get rid of.

"Malcolm is monopolising the vending machine again, no-one can get him to move."
"God! what a fartleberry!"

Fartleberry by AKACroatalin March 12, 2015