Simple Perl script which, in conjunction with a Java script from the ANT consortium's FIT SDK, converts a FIT file to a GPX file appropriate for upload to Strava.
Requires the free FIT SDK from https://www.thisisant.com/developer/resources/downloads/ As of May 2017, the SDK works with FIT versions 1 and 2.
See configuration and usage instructions at the top of fit2gpx