The interval technique known as Fartlek will keep things interesting (and improve your fitness). Fartlek training involves running at different speeds for intervals, but that’s kind of where the ...

Fartlek (Swedish for ‘speed play’) is one of the most common training sessions I use with my athletes. The history of fartlek training dates back over 80 years, when coaches and scientists ...

But of all your exercise options, few will be as effective, simple, adaptable and enjoyably impertinent to brag about as fartleks. Fartleks are an informal version of interval training.