David Hagen plays beach volleyball for SV Kürnach and competes in the federation “Bayerischer Volleyball-Verband”.
Currently listed in BVV U14 Herren 2025 (rank 59, 29 points); BVV U16 Herren 2026 (rank 66, 89 points); BVV U16 Herren 2025 (rank 137, 29 points). Ranking seasons: 2025–2026.