Gustave grew up in Arêches-Beaufort, a mountain village in the French Alps, in a sporting family. He started alpine skiing at the age of 2, then took up ski mountaineering with the Club multisports Arêches-Beaufort, reaching the French youth team: he raced the U18 European Championships in 2024.
He began racing bikes at 16, in 2023, with La Motte-Servolex Cyclisme, the club where he learned to race and is still licensed. After two junior seasons with JEGG-DJR, the junior team of Visma | Lease a Bike, he joined Red Bull – BORA – hansgrohe Rookies in 2026.
His goal: turn professional, become a world-class rider and one day shine at the Tour de France.