What is the purpose of the 1000s that you use with your runners?, I've seen you use it a few times.
AJ, The 1000 repeats starting every 5 minutes are nothing special from a physiological standpoint but it is a standard workout that I use that gives me good feed back on how a runner is progressing. The work out is given like this; run 1-10 times 1000 meter runs starting every 5 minutes and only start the next one if you heart rate is under 125. When a runner starts this workout they usually run about 10 mile pace and do 3-5 runs before the 125 HR stops them. After 3-4 sessions (about a week apart) they will run 8-10 of them at around 10K pace before the HR exceeds 125. I don't look at the times as much as how easily they recover in between the runs. When a runner can do the 8-10 reps with ease they are close to being in peak shape. If they start having trouble with the recovery to 125 (causing them to stop early) either they ran the reps to fast or they had not recovered from the previous hard workouts. From that information I slow down the reps and add more easy running before returning to the 1000s again. By having one signature workout you can get good feed back on what you should be doing between that workout. For women runners I adjust the distance down to 800 meters and with them starting every 5 minutes also (this way mixed teams can run the workout together over two different loops).