Sunday, November 25, 2007

A Run/Walk Pace Calculator

ORN: 7.6 miles, R5/W1, 1:16:45, 10:11/mile; then 5.1 miles, R9/W1, 49:12, 9:34/mile

One sure-fire way to strike fear in the hearts of many people is to ask them to solve a story problem. You know the one from school beginning with “A train leaves Boston at 8:30, heading to New York at 45mph….” Scary, for many.
But not all.

Some of us more geek-oriented people actually LIKE story problems. When I saw one on a test, I always licked my chops, knowing I was going to get lots of credit. Apparently, my blogging buddy Wes has a similar bend. So, Wes and I collaborated on a public service project to solve a particular story problem for all our running pals.

The story problem goes like this. “So, I’m using a run/walk plan in a race. If I want to have a certain pace per mile and have a certain run/walk interval, just how fast do I have to run during my run segments?” You can hear the teeth gnashing over that one.

Wes and I worked through this issue and reduced all the variables to a simple spreadsheet, which we’ve posted on line. You can viewthe Run Walk Pace Calculator or you can download it here. It should allow you to enter your desired overall pace, your walk pace and then learn what your run pace should be. Further, we have two tabs on this spreadsheet. One is a general purpose calculator for the run pace. The other is a race-specific calculator. You’ll get slightly different answers from each one. If you want to know just WHY you’d get a different answer, I’d tell you but that, my friends would involve another story problem and you really don’t want another one anyway.

We’d appreciate it if you could try to open it, test drive it and let us know if it makes sense. It is, after all, a public service and we aim to serve.

I applied this today in my long run, two weeks now from Rocket City. Utilizing David’s example, I took a 7+ mile warm up at an easy pace, then reset my watches and attempted to run the last five miles at exactly the pattern I plan to use in the marathon. The calculator told me I needed to run at 9:22 with a 9/1 sequence to hit the 9:43 overall pace I want for a 4:15 marathon. Could I do that on legs still tired from sub 8 minute miles on Thursday and 7 more miles just before it? I was pleased that it worked. My mile splits for the last five were 9:36, 9:46, 9:33, 9:31 and 9:27. Given that my Garmin usually about 4-6 seconds slow per mile, those are just about right. Can I do that for 26?? Well, as they say, that’s why they play the game.

Enjoy the calculator. Enjoy the laugh at the geeks. Enjoy the cleaned up blog style here; I hope it reads a little cleaner for you now.

And, as always, persevere.

13 comments:

david said...

Looks like your are right on pace. Fourteen days and counting!

Sarah said...

Sounds neat! But I didn't have permission to access the doc.....

Backofpack said...

Joe, I'm dying to check it out, but can't get access. Help?

Backofpack said...

Okay, Joe, now I get to it, but it says "view only". More help?

WADDLER26.2 said...

Joe,
That's a great spreadsheet. I do the run walk also and have tried many times to figure out my walk pace. You've got it!

Take care,

waddler

Wes said...

I have been intrigued with this question for a long time. What piqued my curiosity about your spreadsheet was removing the race distance requirement. Some problems are even better if they have multiple paths to the same answer.

That's an awesome run! I thought you were doing 4/1 for the marathon. 9/1 does mean you get to run a bit slower. I've got long runs of 10 and 6, but I'm done with my marathon pacing. Getting excited. Rocket City hooooo!!

robtherunner said...

I like the idea, but way too high tech for me, Joe! I tend to use the run/walk when and however fast you please method. I remember the days of calculating mile splits. Especially as I slowed late in a marathon and I would figure out how fast I had to run to beat that certain time. Nothing like math on the go late in a marathon to keep you occupied.

Jenny, Maniac #401 said...

I downloaded the calculator and can't wait to give it a try! Thanks!
Jenny

Can Opener Boy said...

Hi Joe,

I stumbled across your blog while looking for interval calculators, and downloaded your Excel spreadsheet. Thanks!

It is not quite what I am looking for -- maybe you could help me? I'm a geek too, and here's what I'm looking for:

Rather than "run 9 minutes, walk 1 minute" I use an interval set of "run 1 MILE, walk 1 MINUTE" -- on moderate training runs I can avg around a 9:00 mile pace for the running and then I avg about 0.07 miles per minute for the walking segments.

I can plug that into a simple column sum, but I'm stymied when I get past 12.84 miles. That last 0.26 miles to get to 13.1 is where I get stuck.

My real question is how fast do I need to RUN during the one MILE segments to get a half marathon in under 2:00:00. I think it is 8:50, which sounds doable...but want to make sure.

I'll eMail you as well, and include the spreadsheet I built, but I'm not sure I got it right...

hope you can help!

Anonymous said...

I just downloaded it and will be using it for the NWM this weekend! I can't wait to give it a try! Thanks

propaganda said...

There is an error in the arithmetic of the spreadsheet to calculate the desired run pace. The calculation makes an assumption that the walk time is always 1 minute. You will get different answers when you double or half the walk/run times - for example 9 min run 1 min walk gives a different answer to 4:30 min run 30s walk - they should be the same. You can fix this by changing cell B25 to =(B23*D12)/(C14+(D14/60))

Tigerback71 said...

The calculator looks great, you're so much faster than me....darn my little legs!

Andrew said...

This is exactly what I was looking for. I was afraid I'd have to write it myself. Thanks so much!