I am 4 weeks away from an important 5k race where i want to run around 15:55min. Tomorrow I wanted to do a session of 20x400m at 5k pace. How much should I rest between the reps and could this be considered as a vo2max workout ? I dont want it to be to intense since I have another workout (8x1000m at around 10k pace) sheduled in 3 days but it should be a good session in preperation for my upcoming races.
Thanks