FIT activity types — every sport a .fit file can declare, measured

Every activity type a .fit file can declare, and how often each one actually appears — counted across the 68,068 real files this parser is tested against. The distribution is lopsided, and that is the point: a reader tuned only to running and cycling is tuned to most of the data and almost none of its edges.

How a .fit file names a sport

Every activity carries a sport and usually a sub_sport — cycling with sub-sport indoor_cycling, running with trail. The parser resolves the pair to one canonical activity, because sport alone cannot tell a pool swim from an open-water swim, and reading the wrong one changes how the distance should be trusted. There are 44 canonical activities below across 4,200 sessions; 12 of the most common have a page of their own explaining what is specific to reading that sport.

Reading your own activity

Whatever sport your file declares, open it here to see its fields — the reader runs on your device and uploads nothing. The activity pages linked above each explain the one thing that sport gets wrong most often, from a running cadence that reads half its real value to a pool distance that lives or dies by one setting.