Today’s workout: 2 mile tempo at 8:41 per mile
It’s hard to believe but today’s post is the 500th since I started The Emerging Runner in 2008. I like having a bit of history to look back upon. My original goal for this blog was for it to be a journal of my experience returning to running. I do use it for that and I find it helpful to occasionally look back on what I was doing a year ago to see if I’ve made any progress or if I’m looking at running differently. I’d say there’s been progress and my view of running hasn’t changed a bit. Both good things.
With all my hill work and trail running over the last week I felt that I needed to do a more speed-focused workout today. Last night I mapped a run that measured exactly 2 miles that I planned to cover at 5K race pace. One reason I kept the distance down to two miles was to motivate myself to run faster than I normally would at 4 AM. Another reason for the exact two mile route was to quickly compare the distance MotionX was mapping compared to my actual, known distance.
The run went well. I didn’t expect to hit a record breaking pace because I generally run about 15 seconds per mile slower at this early hour. The run felt fast and I knew I’d do better than normal (and I did) but I was still disappointed with my 8:41 pace. MotionX, the GPS app I’ve been using on my iPhone, was again way off. It measured the run at 1.86 miles. It’s easy to see why it does that. Looking at the map trace from the GPS signal shows a number of vectored corners and shortened paths that add up to less total distance. This confirmed that the GPS always under-counts distance and today’s margin of inaccuracy told me that it was off by 7%. That’s disappointing and it’s the primary reason that I didn’t buy a GPS watch to replace my Garmin 50. I’ve been told that the Garmin GPS watches are far more accurate than the iPhone but I’ll stick to the foot pod for now.