Anybody that has run with me in the last 10 years knows that I am a firm believer in 800 meter repeats for any distance 5K and beyond. Yasso 800s, in case you did not know, are named after Bart Yasso, who discovered that if he could run 10 x 800 in 3 minutes, with 3 minutes recovery, he was in 3 hour marathon shape. If he could do them in 2:30, with 2:30 rest, then he was in 2:30 marathon shape (Yasso 800s in Runners World).
My only beef with Mr. Yasso is the length of recovery. When I'm fit, I can do the 10 x 800s with 60-75 seconds recovery. Three minutes to recover from a 3 minute 800 is too long, even when you are doing 10.
In preparing for the Seoul Marathon last March, I remember waking up the week before the race thinking I needed a good quality workout, but didn't even feel like running!
Knowing I had to do something, I headed over to the 5 lap per mile track on post and decided to measure off 400 meters on the artificial turf with the GPS. Running just inside the track, I started at turn 4 and found the finish line right where it should be, about 100 meters in front of the start.
With the tight turns, I was managing only 92-93 seconds per 400. Certainly nothing to brag about, but remember I didn't even feel like running in the first place. For recovery, I jogged the 100 meters back to the start, and after 10 I noticed on the GPS that my average time was right at 7 minutes per mile. That sounded better than 92-93.
Instead of running the 400s faster, what I tried to do was bring down the average pace by increasing the speed of the 100 meter recovery jogs. For some reason that idea really clicked, and I was able to finish off the next 10 with a final average time of 6:45 per mile, totalling 6.5 miles.
I'm still a fan of Yasso 800s, but I will definitely revisit this workout when preparing for my next big race.