4 / 4 X 800S
WHY For new and intermediate runners, half-mile repeats help you gauge your speed without worrying about pacing yourself over a longer distance.
HOW After a warmup, run 800m at a comfortably hard pace. Adjust pace in the next three reps depending on how you feel (take a 5-min walk between each). Take the average pace of your reps to find your 5K goal pace. Over three months, increase the reps to five or six, or decrease recovery.