Race Time Equivalents

The worldwide web boasts a handful of race time predictors.  The premise is simple: enter a recent race time, click on "calculate", and the predictor gives you a slew of equivalent performances at other distances.

Obviously, there are a lot of factors these calculators don't take into account, such as race courses, weather conditions, training peaks, training focuses, tapered vs. un-tapered performances, individual strengths for certain distances over others, etc.  To me it seems like they are typically more accurate for men when going down in distance (i.e., a male inputs his 10K time and it will pretty closely predict his 5K time), and for women when going up in distance (i.e., a female puts in her 10K time and it will pretty closely predict her half marathon time).  In general, I think they are more accurate one way or the other (going up or down in distance) for each person, but usually not both.

For me, they have always been more accurate going up.  I used to be able to put in my half marathon time, and the equivalent marathon time would be pretty close to, or just slightly slower than, what I'd end up running in the marathon.  For example, in 2010 I ran a 1:28 half and the calculator predicted a 3:04 full; I then ran a 3:03 full.  The predictor also said I could run a 19:15 5K with that half time, and at that time any day I saw 19:5X in the 5K was a good one!  As I've worked my half marathon time down in the past 1.5 years, I haven't run an equivalent marathon.  I've also had pretty ideal conditions and courses for a few halves, but have not had ideal conditions or run a great course for a marathon, so I'm hoping my marathon day is coming - if not in Phoenix, in the fall...if not in the fall, in spring 2018...(I am persistent if nothing else!).  The same goes for my official 10K PR, especially because I keep beating it in tempos and half marathons!

My favorite predictor is Jack Daniels' VDOT Running Calculator.  I obviously take its advice with a grain of salt, but at the same time I'm always excited to plug new PRs into it and see what it spits back at me!

When I put in my half marathon PR of 1:21:26 (run on 1/15/17), this is what I got back:

Initially I laughed, and said, "I don't have any of those other times in me!"  Looking a little closer, I decided I think I do have that 15K in me since I've done an 8 mile tempo solo at a 6:06 average.  I am still pretty skeptical about the rest, but my half PR also taught me that I need to stop being afraid to go for it.  When I ran that half, I basically went out with the goal of running 13.1 miles at 1 second per mile slower than my official 10K PR, which seems like something anyone with half a brain would be skeptical of.  I hadn't raced anything that indicated I could do it - but I knew I could do it, and I did (actually 1 second faster per mile than my 10K PR average pace in the end).  I think under ideal conditions and on good courses, I do have those times in me for the 10K through the marathon.  Now that 5K prediction - absolutely not, haha!  I'm just looking to break 18:25 there (this will most likely first, and possibly only, occur in the second 5K of a 10K).

This calculator also shows that my half PR is currently my strongest PR, which I kind of already knew, as all of these equivalents are faster than my PRs at other distances.  My current training has made me strongest for halves, which is kind of humorous since it's actually marathon-focused.  I think it comes down to the tempo work I've done helping my stamina and speed, the marathon-training long runs giving me strength to power through 13.1, and my mileage being most conducive to a strong half but not enough for my strongest marathon.

I recently read an article regarding training to break 3:00 in the marathon, and it recommended running 90 miles per week (mpw) and running every single day in order to do it.  I did not do anywhere near that before my sub-3:00s; I averaged in the mid-50s for mileage and alternated weeks of running 5 days with weeks of running 6 days a week...just this training cycle is the first my coach has had me run 6 days a week every week, and my Friday runs are a measly 3 miles, which I am not even sure counts (I really appreciate his conservative approach, though, and it's keeping me healthy).  Then I used this calculator, which gave me a marathon predicted time of  2:49:47 from my half time when I did not input mileage, but the prediction jumped to 2:57:28 when I put in an average of 60 mpw, which is about where I'm at this cycle (later note:  my average was actually 57).  Then I played with it and basically found out that I am supposed to average 90 mpw to be able to run a 2:49.  Oy! 

Anyway, we will see what I can do in regards to these marathon and 10K equivalents on February 25 and March 31, respectively.  Then I'll re-visit my hypotheses on these things.