ANT Forum

All,

I'm trying to make sense out of a fit file generated by an edge 520, and cycling performance data. I'd like to download a timestamped datastream of the following data recorded by the device:

1. wattage
2. speed
3. grade
4. heartrate

in other words something of the format:

relative time(min) speed grade wattage heartrate
--------------------------------------------------------------
0, 15, .5, 240, 130
1, 14.5,-1,230,135

so I can get fine grained performance metrics of my bike-ride, graph this data, etc.

However, when I upload to services to convert such as http://www.gpsies.com/ I see, that the only thing they do convert in a timestamped way is the gps data. Which is great but it is exactly what I am not looking for.


Is this data available in the fit file? I would find it incredibly hard to believe (and annoying) if this fine grained data that is showing on the device isn't actually saved anywhere in the fit file but before I would dive into the SDK I thought I'd ask people here any insight they might have.

Thanks much for any help,

Ed      

Hey Ed,

Power, Speed, Elevation, Location, and Heart Rate are all stored in the record messages within an Activity File. This message is time-stamped and written regularly throughout an activity, so using the SDK to consume a FIT file should be able to generate the data you are looking for.

You may need to do some calculations using Elevation and Distance to retrieve Grade.      

caufield,

first thanks for the quick reply.. I scanned the FIT SDK docs and it wasn't really apparent there so this does help..

Just curious though, is there a utility to convert a full FIT file to a generic data format like JSON, without abridging the data in it?

if this didn't exist i'd be very surprised (if nothing else not to support REST apis) and it would be a ready answer to these types of questions.

ed

(ps - hm, answered my own question: https://github.com/mrihtar/Garmin-FIT - hoping that is fully generic unlike http://www.gpsies.com )