Originally Posted by
Marco
Whilst I think your theory is good, you will always be slower at 5km than you are at 1km. For this reason I would suggest you try 4 x 1km at 3:30/km pace. This is also a more ambitious target of 17:30.
On a broader training subject, it is worth mentioning that every speed of running, (whether it's 3:36/km or 3:30/km), will have a slightly different optimum technique for you. Unlike cycling, where your legs rotate in a fixed orbit, the path of your legs and the neuro-mechanical firing of the muscles alters. One of the main reasons for doing shorter intervals at race speed is to learn the optimum technique (for you) at that speed.