6x200m at moderate pace w/ 200m easy jog
6x300m at moderate pace w/ 100m walk
6x400m at moderate pace w/ 60sec rest
Workout Details: ALL of the moderate paced intervals are at the same pace. I would recommend selecting a 200m time for your opening set about 5sec/200m slower than your mile PR pace.
As example, an athlete with an 8min mile PR would target ~65-66secsec for their 200m intervals. Every set thereafter would also be at the same 65-66sec/200m pace.
Expect this workout to get progressively more and more difficult (especially if you pick a fast opening set pace).