Your thoughts on 12 x 400m at 5K pace w/ 15 sec. rest as a staple 5K workout?

I gave the workout an honest effort last night. First time attempting it. I've done quarters before at mile pace w/60 second rest but never at 5K pace.

What I found was interesting. It wasn't as hard as you'd think. The biggest challenge was resetting the watch and being ready to go in 15 seconds but apart from that, it wasn't any more painful or race-like than doing 4 x 1 mile at 5K pace with 3 minute rests. In fact, I still respect the mile repeat workout more.

I was able to hit target pace on all 12 quarters. 85 seconds for each rep which is my regular 5K training pace. The last one I ran in 84 so it wasn't like I was beginning to fade either.

What I like about the 400s is how your heart rate stays elevated. You begin the next rep feeling like you're "not quite ready" but then you settle into your rhythm again. The first 200 go by with very little strain. I think it teaches relaxation at goal pace and the short rest is more race-specific.

I a little surprised by that, but I think that affirms for me one of the things that I suspected - not a staple workout, but something that you might want to do on the front or back end of a big vo2max training block.

Interesting...thanks for posting your experience.