Speed on a reach vs upwind/downwind. Wind. Lots of wind.

Another perspective:
www.riwmag.com/defi-wind-superstars-2020-d1-epico/?lang=en"evin Grosjean, Jordy Vonk, Bjorn Dunkerbeck and Andrea Cucchi then slipped forward in the first third of the course. But once behind the island, the downwind edge allowed the foilers not only to return but also to take the lead despite the extreme conditions. In a chaotic backlash, superstars have gone into survival mode like Pierre Mortefon "I wasn't sailing against the others, but against myself" testified. Andrea Cucchi was forced to stop for 20 minutes. "I've had the hardest day of my life in windsurfing, my heart was beating at more than 200!"