[1] Julia Tannheimer made her international debut at the 2022 Youth World Championships in Soldier Hollow, Utah.

She also participated in the Youth Olympic Festival in Forni Avoltri, where she won gold in the individual event and silver in the mixed relay.

Tannheimer excelled at the 2023 Youth World Championships, winning convincingly in the sprint and pursuit with the fastest times.

After two top-ten finishes in Idre, she achieved a remarkable feat in Sjusjøen, winning the mass start 60 despite three shooting misses, becoming the youngest winner of an IBU Cup individual competition in history at 18 years and 137 days old.

[4] On January 12, 2024, Julia Tannheimer made her debut in the Biathlon World Cup at the sprint event in Ruhpolding.