Given my inability to make a decision to switch completely to Nike+ from Sports Tracker, I have developed a solution to export Nike+ runs as GPX files which can be easily imported into Sport Tracker (manually). It is a Chrome plugin, which will login into Nike+ and then list your runs, and next to each run is the ability to export to GPX files.
Caveat – Nike+ doesn’t provide an interface to give the exact time at each GPS location, so I use the split data (1 kms) to average each GPS location over each KM (i.e. profile/lap data is accurate only to a 1km resolution).
There are other sites around that provide this kind of feature, but the latest Nike+ update broke most of them (at the time of this post). Therefore, this is the only option I have which works with the current Nike+ as of August-2012.
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