I'm sure most people here have gone through a period where workouts have been going well, but races have been bad. My PR is 14:50 and the workouts I am able to do now are about even with my workouts leading up to my PR 2 years ago. At this point I have had multiple races over 15:20 (or equivalent). I'll go out around PR pace (because my training indicates I should) and feel O.K. for the first half, but gradually slow down after that.
Does anyone have any advice on what I should do? Do I need to take a break? Physiologically, how is this even possible? I can't put a finger on what is different between now and when I was doing virtually the same training two years ago.