[Scott Johnston]

Congratulations on your 5:45 mile. I’m sure there are still a lot of improvements that would be possible for you if you had given more time. If you redid your aerobic threshold test, you may now find that your aerobic threshold running pace and heart rate have increased above the 9:30 you most recently hit. I agree that most of your aerobic threshold pace and heart rate improvement has come from the aerobic base training you’ve been doing. You shouldn’t cut back on that volume in order to add more intensity. I would continue to keep the hill sprints and strides in your weekly training.

There are several ways to maintain that 6 minutes per mile with one workout per week. The simplest one would be to do one tempo run each week at about 85% of your current 1-mile best time. Run as long as you can at that 85% and notice when the speed begins to drop off. The next week, do the same thing. You should find that you’re able to hold that 85% for 30 to 60 seconds each time you do it.  You could do this during your long weekend run.

Another way would be to dedicate one workout a week to doing mile repeats at about 90 to 95% of your current best mile time.

I hope this helps,

Scott