A tempo run at the track, with the goal of having a conservative first repetition, and at least 20 minutes of total quality running. The first 1600 ended up being so conservative, I lacked concentration, and was day dreaming during the last 1200m.
1k warm up
A few drills with strides
3 X 1600m with 1:00 rest between (6:13, 6:06, 6:09)
1 X 1000m in 3:49
These types of reps are what Jack Daniels calls cruise intervals. I like that nomenclature.