When skiing - especially carving ski - it'd be interesting tracking the acceleration (low-pass filtered below 1Hz or so) along speed and other figures.
Based on the v²/r formula, this acceleration can easily go up to 3g or more (!); e.g. 70km/h carving turn on 12m-radius slalom skis.
Such acceleration figures could give valuable hints on the muscular efforts and overall exertion, especially given: 1. such accelerations can be sustained up to a few seconds (long carving turn) and 2. repeatedly (such carving turns are the essence of carving skiing).
Thanks for considering this suggestion and best,
Cédric