Lactate Threshold Training

I like using timed runs instead of a distance myself. Not saying any is wrong or not, but I like the idea of a timed effort for the overall race time goal. If you aim to run 50 seconds, do a 50 sec hill run. The idea of a hard 50 sec effort gets instilled early in training plan. My HS girls do 60 seconds, as they run 63-65 range. My boys do 50 as they were 51-52 range. I found nice progress throughout the GPP on hills. We had land marks to gauge progress each session we did it.