OptionalcreatorWhat the file says made it: a FIT file_id's maker (FIT's name, e.g.
"garmin", or its number) and product number, and a product or
creator name (FIT product_name, TCX <Creator><Name>, GPX
creator). As stated; turning a Garmin product number into a model
name is left to the app.
OptionallapsOptionalrecoveryHeart rate after the stop, when the file has it (a Garmin watch's
two-minute recovery_hr reading).
OptionalswimA swim watch's own record (pool, lengths, swim time), when it has one.
OptionaltimerTime the recording timer ran over the whole activity, as the file
states it (FIT session total_timer_time). Absent when it doesn't.
An activity together with its streams — the shape an import yields. Laps are present only for sources that record them (FIT); GPX/manual omit them.