I am now entering my seventh week of marathon training.  Part of my weekly regimen is to spend every Wednesday night engaged in some form of interval/speedwork.  Up until last Wednesday, I was working on a series of progressively longer distance intervals, starting at 1000 m reps in week 1, and working my way to 2000 m reps in week 5.  As a treat in week 6, I was rewarded one of my favorite speed/interval workouts – the Yasso 800!

Yasso 800 – one of the most controversial workouts in marathon running.  Conceived by Runner’s World contributor and marathon runner Bart Yasso (for whom the workout is aptly named), the theory behind the Yasso 800 is simple – a runner can effectively speed train for a marathon  by running a series of 800 m intervals in the mins/secs that correlate to the hours/mins of the marathon’s finish time.  For example, if I want to run a 3:58 marathon (and qualify for Boston!), I should run 4-6 800s in 3 min, 58 seconds per rep.  Each Yasso 800 should be followed by the same period of rest/recovery. 

Some runners believe there is no corrolation between the Yasso workout and one’s actual marathon finish time.  Others swear by it.  I had the opportunity to meet and speak with Bart Yasso at the Marine Corps Marathon, so I asked him why the workout was effective.  His answer:  “I’m not really sure…but it has always worked for me.”  I had to laugh, but it made me think…what did I get out of the workout? 

I’ve incorporated Yassos into my training for several years.  When races have gone well, the predictive outcome was remarkably close.  In years where it hasn’t worked so well, it’s usually because some other environmental or external factor has derailed the run and adversely affected my performance.   At a minimum, the Yasso 800 allows me to focus on pacing, build my aerobic capacity and above all, take a mental break from longer intervals and grueling distance training  runs. 

Looking to improve your speed and add a bit of variety to your half or full marathon training schedule?  Throw in 4-6 Yassos every few weeks.  And take a tip from a veteran—really focus on pacing and  turning in consistent times for each Yasso 800.  The first time I did the workout, I foolishly ran the first set about 15 seconds faster than required.  By the third Yasso, I could barely make the backstretch from 600-800 m!  Lesson learned—the Yasso may be a useful predictive workout, but for me, it serves as an important tool to focus on disciplined pacing and speed.