Lena Häcki competes for Nordic Engelberg . She took part in her first Biathlon Youth World Championships in 2012 in Kontiolahti and achieved her best placings with 43 ranks in sprint and pursuit. In 2013 in Obertilliach, 44th place was her best individual result. With Tanja Bissig and Sabine di Lallo , she also won the bronze medal in the relay race. In 2014 , Häcki achieved top ten placements in individual races for the first time in Presque Isle with eighth place in sprint and pursuit.
2014/15 season
In Beitostølen , Häcki contested her first women's races in the IBU Cup at the start of the 2014/15 season and won her first World Cup points in sprint races in 33rd and 37th. Since a place in the World Cup team had become vacant due to Selina Gasparin's pregnancy , Häcki competed with several other young Swiss runners for this position and was appointed to the Swiss World Cup team for the second World Cup station in Hochfilzen . In her first sprint race, as 89th, she missed both points and the pursuit. A week later, she managed to qualify for the pursuit race for the first time as 58th of the sprint in Pokljuka , in which she was 55th. At the first races of 2015 in Oberhof, Häcki started as a starting runner with Aita Gasparin , Flurina Volken and Ladina Meier-Ruge for the first time in a relay race in the World Cup and was 15th with the young Swiss team in difficult conditions. She won the sprint two days later as 30th her first World Cup points. On January 23, 2015, she achieved 12th place in the sprint in Antholz, the best result of her career to date.