If you don’t know what Yasso 800s are, you can listen to the man himself (Bart Yasso) explain how doing ten 800-meter repeats with 400-meter rest intervals in between can predict a runner’s potential marathon finish time: Yasso 800s.
I’d never done them before until today, when my workout called for 12x800m. After a one-mile warmup, I did 10x800m and called it good based on the time I had to do the 8.3-mile workout. I later determined that my pace averaged out to 3:34 per 800 meters. If you believe the ability of Yasso 800s to predict marathon finish time, that means I could finish the marathon in 3 hours and 34 minutes, which would be a 10-minute PR for me. That time is also what the McMillan Running Calculator predicts I could do the full marathon in based on my half marathon time at Revel Canyon City, and what the Marathon Time Converter says I could do at the Phoenix Marathon based on my 3:44:26 finish time at the Santa Rosa Marathon (which you might recall qualified me for the Boston Marathon but did not meet the cutoff to get me in to the race for 2015).
So, with 10 days to go until the Phoenix Marathon on February 28, this workout was just the confidence booster I needed. Tomorrow calls for 30 miles on the bike plus 20 minutes of strength training, and Friday calls for an 8-mile tempo run. After that it’s an easy “long” run of 6 miles (one mile warm up on Sunday morning plus the Brea 8K) and then an easy week of taper until the Phoenix Marathon on Saturday, February 28. Whee! After 5+ months of training, it’s hard to believe it’s almost here!
intermediate marathon training plan, and I think it called for the King of All Speed Workouts because this week’s “long run” is replaced with a “long bike” of 60 miles. That will be a new personal distance record for me on the bike, by the way. Just a few weeks ago I did 50 miles in 3 hours 15 minutes. I confess that during that time there was never a moment that I said, “Gee, I really wish I were running 20 miles instead of biking today.” 
Fit Fun Mom 