A blog by runners. For runners.

Calibrating the iPod Nano Sport Kit

I finally made a point of calibrating the Sport Kit this morning after over 5 weeks of threatening to do it! I decided to run downtown to the track at Lake Shore Park where it is rumored Oprah trains. According to my math on WalkJogRun it should be 4.21 miles each way. I reached the track in 34:25 but the Sport Kit expectedly overreported the distance at 4.57 miles. It was 85% humidity for the run according t the weather channel before I left so I made sure to stop and grab water at the fountains every mile or so. At one point I ran towards a fountain but I misjudged the rough ground at the side of the path and turned my ankle. After a couple o stretches I was able to begin running again without pain. When I reachd the track I was suprised to discover that the fountain by the track was pumping out hot water for some reason.
After catching my breath I started the calibration process. To calibrate

  • select “Nike+iPod” from the main menu on the iPod
  • select “settings”
  • select “sensor”
  • select “calibrate”
  • You see some instructions about how to set your natural running and walking pace for calibration purposes
  • click the center button to continue
  • You see an option to calibrate your walk or run pace
  • select “Run”
  • You can either run 400m if you are at a standard track or select Custom to select your own distance
  • select “400m”
  • select a playlist and then when you are ready it prompts you hit the center button to begin calibration.
  • at the end of your 400m track hit the menu button then select end calibration to finish

I double checked the run I had completed on the way to the track but it still showed the same distance and pace so it must only work for runs completed after calibration. I would like Nike to add a feature to their Nike+ website to allow you to apply your calibration to a selection of runs in your history. For example, I don't imagine that if I had alibrated the unit when I bought it and then again today, I don't imagine there would be a significant difference so I would actually prefer the site to update selected runs to reflect a correct pace and distance.
Since I know I tend to walk at the pace of the terminator I decided to calibrate my walking pace too – I'm not sure if it helps tune the unit even further but I doubt I'll be back at the track in the next 5 weeks so I thought it was worthwhile.
After heading inside the Park District Office on site for water from a cold fountain I walked back to the lakefront path. I stood and watched some of the people training for a triathlon swimming up and down from North Beach and then ran back at a deliberate 9 minute mile pace. Immediately I noticed that the pace reported by the iPod Sport Kit seemed far more plausible and it was easy to hold up and stick to 9:00 per mile. Taking in water at each fountain to accomodate for the humidity I felt great heading home to the point that when I saw my building as I turned the corner by the dog beach I hit the “power song” button to boost my speed for the remainder of the run. Bounding along to Outkast's “B.O.B” I upped my pace from 9 minutes per mile to 8 minutes per mile and finished in 38:12. The iPod reported 4.3 miles – much closer to the 4.21 miles than before so it seems the calibration really does improve the accuracy.
I've just finished my breakfast as I write this and taken 2 advil to help with any swelling caused by twisting my ankle. Hopefully I'll be able to get out tomorrow morning too and see if I can creep closer to my 80 mile goal before the deadline next Friday. Basically I have 5 days left to run 35 miles or 7 miles per day. Hmmmm. Like I said yesterday – it's a little disappointing not to hit the target but 80 miles in 4 weeks was always going to be an aggressive target so close after my first marathon.