*** Run at an even pace (flat course) use cumulative pace for the Km on your GPS device. If you can run any part of the last 1km faster than the earlier 4km then you weren’t running the 4km fast enough. Try harder next time (gulp!)
All the suggestions are starred:
*** 3 stars. IMHO it will work
** 2 stars. It might work
* 1 star. Can’t hurt
X 1 cross. It CAN hurt if done wrong.
All 50 tips are shown here as a series of posts : http://the5krunner.com/tag/how-to-get-a-5k-pb/ or on twitter using #howtogeta5kpb. They are all SHORT-TERM tips that will work in the next week or so with varying degrees of success.