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From Fellrnr.com, Running tips
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* The measurement ride started at one end with the wheel on the end of the asphalt. The first measurement was after 1/8 of a mile, then every 1/4 mile until the last marker that was at 1/8 mile. Permanent markers were placed at each interval.
* All tangents were taken within the required 12 inches of the apex, aiming for approximately 6 inches which reflects my usual distance from the edge of the asphalt.
In addition, I verified the course using a surveyor's wheel, measuring each segment of the course twice. All measurements were within a few inches, confirming the accuracy.
=Data Gathering=
On first usage, a watch is left on and with GPS acquired with a full view of the sky for ~45 minutes. This is to ensure the watch can download the full ephemeris data (it should only take 12.5 mins, but I want to be sure.) To prevent per-run startup problems each device was turned on, satellites acquired, and then left for around 5 minutes before the run starts. This is to counter the problem of a device claiming to have acquired the satellites when it only has a minimal lock. The watches are worn on the left wrist or held in the left hand in roughly the same orientation as it would be on the left wrist. The lap button is pressed as I passed over the marker, and if it is not possible to press at the correct time the lap button is not pressed until the next marker. (Software will reject the data from missing lap marks.)
=Initial Data Preparation=
Some preparation was required to allow for subsequent analysis.
=Data Extraction=
The software uses the TCX format for analysis. Many devices provide TCX files by default, but others require conversion.
=Data Analysis=
The analysis process uses an application I wrote in C#.
