So many great speed Workouts on this website, this is probably what I need the most, I can run forever, but I struggle to keep it below pathetic 8 min mile pace when I get over 3 miles so I hope to train a little smart. My question pertains to fartleks and how I saw on this site ideas for sprinting (or hard running) intervals between 100m-800m and I have also seen (and I had heard before) that you should really be exerting on fartleks for about 3-4 mins at a time. To me this means that maybe on a fartlek my 8-12 high intensity burst should be no shorter than 600s and potentially longer than 800s? Anyways I would appreciate any help with distances, variety, etc on what people think about this, thank you all for your time.


Keith