A keen horse rider and tetrathlon competitor from an early age, Bryson was inspired to get into modern pentathlon when she attended a pony club demonstration by 2008 Olympic silver medalist Heather Fell.

[8][9] Again in Drzonków, later that year she won silver medals in the individual and women's relay events as well as bronze in the team competition at the 2019 World Junior Modern Pentathlon Championships.

[10][11] Stepping up into the senior ranks, Bryson won a gold medal alongside Myles Pillage in the mixed relay at the 2019 European Modern Pentathlon Championships on home-soil in Bath, England.

[15] Bryson won her first World Cup medals in Sofia, Bulgaria, in May 2023, taking gold in both the women's individual as well as the mixed relay alongside Charlie Brown.

[16][17] In August 2023, Bryson won a bronze medal at the Modern Pentathlon World Championships and in doing so she secured Great Britain a quota spot for the 2024 Summer Olympics in Paris.