arch injury - plantar fasciitis

You're probably not going to want to hear this, but you bought the wrong running shoes.  I've been down this same road, other foot though.  You will need a shoe with more arch support, or possibly an orthotic support in your current shoe.  Also, make sure that the heel cup is quite snug when you buy a shoe.  Repeated pounding of the heel strike when you're running tends to flatten out the pad in the heel of your foot and it wants to displace itself sideways, stretching the tendons and causing the pain you're feeling.

The cure is to make sure you stretch it in the morning and before running.  I'd also look into a different running shoe and an arch support as well, one with a hard plastic or carbon fiber insert.  You might also want to put one in the shoes you use during the day.  Another good exercise to help cure the problem is to roll the arch of your foot back and forth a golf ball.  Do it while you're sitting watching TV or on the computer.  Rest your foot as much as possible, take some time off from running if you have to.  Run on soft surfaces like trails instead of pavement.  All this information comes from my orthopedic surgeon, who is a marathoner and a triathlete!

Actually that's the basis behind the "Pose Running Method" where he tries to convert you to that very technique.  There's more to it than I can list here, but it boils down to running with a mid-foot strike instead of landing on the heel.  You almost feel like you are constantly falling forward and your feet are landing underneath your body instead of out in front.  Do a web search on the Pose Method, I'm sure you'll see a ton of information.  There is a book available too, and DVD/VHS instruction, and there was an article about it in a recent issue of Runner's World Magazine.

OK, I've taken my own advice...here's some links!

http://www.posetech.com/

http://members.toast.net/joe.sparks/pose/home.html

http://www.trymysport.co.uk/pose_running.htm

http://www.triathlete.com/art.asp?3=236

I had it several years ago.  Excruciating pain in the heel when first walking in the morning, but oddly enough little or no pain when running.   I laid off running for a week or two, added a heel cup, then started back with reduced mileage.  I also changed the heels on my regular street shoes.  They were worn down and I  think that contributed to the problem.  I make sure to retire old running shoes before they lose their cushioning.  All of this helped me and I have not had the problem again.  In fact, I no longer need the heel cup.  Don't know if it helped or not, but I've used Asics Gel  running shoes and am very happy with them.

Hope yours is a minor ailment and goes away soon.