Beth Skwarecki is Lifehacker’s Senior Health Editor, and holds certifications as a personal trainer and weightlifting coach. She has been writing about health for over 10 years. Fartleks are a ...

Fartlek – the Swedish word for ‘speed play’ – is one of the most common training sessions that I use with my athletes. The history of fartlek training dates back more than 80 years, when coaches and ...

I don't think that running coaches need to be high-performance runners themselves. I don't even think they need to run at all, at least not for their whole lives. However, if a coach is not currently ...