His effort was impeded by strong winds and light rain, a fact that benefited first and second placed Mads Würtz Schmidt and Maximilian Schachmann, who both started earlier in the day.

[13][14] On 14 September 2016, Kämna won the gold medal in the under-23 time trial event at the European Road Championships in Plumelec, France.

[17] Kämna took his first senior individual race win at the 2020 Critérium du Dauphiné, where he won the fourth stage.

Shortly afterwards he rode the 2020 Tour de France, where he took his first Grand Tour stage win on stage 16 of the race, attacking a reducing lead group on the penultimate climb and being joined by Richard Carapaz, and subsequently countering an attack by Carapaz and building up a lead on the descent and the last climb to win by one and a half minutes.

[18] He had previously narrowly missed out on the win on the thirteenth stage of the race, losing out in the final sprint to Daniel Martínez at the summit finish on Puy Mary.