This isn't my workout but my friend's, he was trying to figure out what shape he's in so I figured I'd go here
2:46 800 threshold then
16x400m repeats 65 average with 200 walk-200 jog recovery
400s - 63, 66, 65, 65, 63, 65, 65, 65, 65, 66, 65, 65, 66, 66, 67, 64
Other details, around 35-40 mpw and recently split 4:33 in a relay leg solo