Fartlek runs can be a fun and versatile addition to any runner’s training plan. In this article, I’m going to cover everything you need to know about this adaptable workout so that you can avoid the potential pitfalls and get the most out of each session.__CONFIG_colors_palette__{“active_palette”:0,”config”:{“colors”:{“65ae6”:{“name”:”Main Accent”,”parent”:-1},”b4975″:{“name”:”Accent Light”,”parent”:”65ae6″,”lock”:{“lightness”:1,”saturation”:1}},”7cdb1″:{“name”:”Accent Dark”,”parent”:”65ae6″}},”gradients”:[]},”palettes”:[{“name”:”Default”,”value”:{“colors”:{“65ae6”:{“val”:”var(–tcb-skin-color-0)”},”b4975″:{“val”:”rgb(250, 252, 255)”,”hsl_parent_dependency”:{“h”:211,”l”:0.99,”s”:1}},”7cdb1″:{“val”:”rgb(14, 28, 47)”,”hsl_parent_dependency”:{“h”:215,”l”:0.12,”s”:0.55}}},”gradients”:[]},”original”:{“colors”:{“65ae6”:{“val”:”rgb(55, 179, 233)”,”hsl”:{“h”:198,”s”:0.8,”l”:0.56,”a”:1}},”b4975″:{“val”:”rgb(251,