For the last couple years I have been running and training for longer distances up to and including a Marathon,
I now want to concentrate more on running 5k's, with the odd 10k thrown in.
I have started on a 12 week plan for a faster 5k from the web which includes lots of interval training and a few fast hill sprints. I've just realised that instead of the slow twitch fibres that are engaged in longer slower runs, I now need to engage the Intermediate and fast twitch fibres... has anyone else come down from the longer distances lately, and how long did it take you to knock a sizeable amount of time off your 5k time. Any advice would be good.