How Fast Can I Run?

As a race day approaches, runners inevitably begin to ask themselves:  "How fast can I run the race?"  This is particularly true of marathoners since if you are like most entries, you have not run a full distance while training.  (Some athletes run the full distance training, but certainly not full out, so this same discussion applies.)  So how fast should you shoot to run the race, and at any point in time, how fast could I run a particular distance?

Finish:  Boston Marathon 2005

My old standby is to use the Runner's World Time Predictor which you can find at the bottom of the post.

I actually have a spreadsheet where I can use various training runs and races (if I did any) to predict a time.  Then from these I can average them, or even calculate a range of possible outcomes and adapt depending on how I am feeling on race day.  So how does the formula work?  As quoted from the article:

"The formula was originally devised by Pete Riegel, a research engineer and marathoner, and published in Runner's World, most recently by Owen Anderson in 1997. It has been widely used since then. The formula is T2 = T1 x (D2/D1)^1.06 where T1 is the given time, D1 is the given distance, D2 is the distance to predict a time for, and T2 is the calculated time for D2."

So how fast will I run this marathon?  Somewhere around 4  hours.  I estimate this using a hard half marathon training run from a couple weeks ago.  Granted:  this run had a huge hill in it and my race will be flat, and I could have run faster.  But nonetheless, this won't be far from the truth.

Training Run Date	1/9/11
Training Run Length (Miles)	13.1
Training Run Time (hours:minutes:seconds):	1:59:37
Please estimate my time for (Miles):	26.2
Predicted time (hours:minutes:seconds):	4:09:24
Split Time	0:09:31

So, barring any drastic changes between now and the race, I'll be running a slightly slower than a four hour marathon.  If I am feeling good as the race approaches, I'll prolly try and run it a little faster, perhaps 9 minute splits and get in under 4 hours.  That depends on how easily I want to recover and that's a whole different topic.  The difference between recovering from a sub-four hour and a 4:15, let's say, research shows, is like night and day.  Again, another topic.

A final note:  this predictor can be used to predict split times for training runs as well.  So if I need to know my 10K pace at any point in time, this is one reference point for estimating that.  Also this equation does not include temperature as a factor.  That will be a topic for a separate post.

RW's Race Time Predictor