Hey Math Majors

check it out ->http://www.jeffgalloway.com/training/walk_breaks.html

for a 12 min / mile, galloway recommemds 2mins of running for every 1 minute of walking.  He states that when one walks fast for a minute, one will lose about 15 seconds over running at their regular pace.  But if you walk slowly, you'll have lost only about 20 seconds.

I'm going to try to do the math now and will post it in a minute but I'll guess that you should run about 11:50 mins/ mile (5.07mph) and walk about 17:30 mins/mile (3.5)

If you have a GPS computer (Garmin, Polar, etc.) you can hit the lap button every time you make a change, then, when you downlod the info, you will get an average pace for each "lap".  Another option is the Nike + system.  As far as doing it without fancy equipment, you would have to go ahead and change what you are doing just a touch, or use some really good planning. 

You could use landmarks to change your pacing.  Say you start your run at the intersection of 1st Ave and 1st street and you run for a minute or close to that to 1st Ave and 5th Street.  You start walking and go for two minutes to 1st Ave and 7th Street, repeat a few times so you get enough data to make sure you know that you are not overdoing your normal pace for a short period of time.  You will have to use a stopwatch and carry a small pad to write the times down (I would do this during the walking phase, since it would be easier and prolly simpler to read later).  When  you have enough data, sit down with whichever mapping software you use (BT's works great), and plot the distances that you did each step earlier and compare with the times.  You could then figure the pace for each leg and see what kind of average you are coming up with. 

The problem with this is that it is going to change as you get more fit, but you will see that as you go more distance in the same amount of time. 

The problem is that you can run a little faster and walk a little slower so that it can still average out to 12 m/m.  Here is a formula for run pace (PR) given walk pace (PW).

PR=4*PW/(PW-8)

Given any walking pace greater than 8 minute per mile this will give the corresponding run pace.  Plug in a fast walk, say 15 m/m for PW, you get at brisk 8:34 m/m pace.  For a slow walk, say 30 m/m, you get lung searing 5:27 m/m pace. 

An interesting thing happens at a walking pace of 8 m/m.  Admittedly that is a pretty fast walk.  In the two minute walking time at that pace, you have covered as much distance as a 12 m/m average pace permits, so you have 1 min running time yet to go but no distance to cover.  You have to go infinitely slowly to make it average out.  Fun stuff. 

Have fun out there and do your math homework.  It might come in handy.

TW