Van Der Zwalmen started playing squash at the age of 8 whilst living in Toulouse, France.

Van Der Zwalmen captained the French team to the 2013 Women's World Junior Squash Championships in Wroclaw, Poland.

For the first four years, the event was dominated by Claire Fahey, who did not enter in 2015 due to a scheduling clash with the real tennis US Open.

The first Ladies Doubles World Championship was held in 2020, which Van Der Zwalmen lost to Tara Lumley and India Deakin while partnering Louisa Gengler-Saint.

Nonetheless, Van Der Zwalmen returned to Queen's for the 2022 World Championship against Schoolgirl champion Cesca Sweet, winning 3 games to zero.

In their first meeting in any singles competition since the inaugural edition back in 2015, Fahey opened with a strong start by winning the first two games and building a lead in the third.

[13][14] She debuted in the 2017 French Open in Paris, losing her singles in the first round to Dutch champion Saskia Bollerman.

She also entered the Men's division of the British Open, the second woman ever to do so behind Fahey, but lost her qualifying match to Freddie Bristowe.

2022 saw the delayed edition of the Real Tennis World Championship held in Van Der Zwalmen's home country of France at the Palace of Fontainebleau for the first time since 2013.

Van Der Zwalmen, despite never having participated in a real tennis World Championship before, was keen to defeat incumbent champion Claire Fahey, so only entered the singles competition.

[19] Another World Championship was held in 2023, this time at Fahey's home court of The Oratory School in Woodcote, Oxfordshire.

[20][21] Van Der Zwalmen also competed in the US Open for the second time, reaching the finals of the singles and doubles draws.

[22] In 2024, Van Der Zwalmen captained the Rest of the World team in the second edition of the Ladies Bathurst Cup at the Royal Melbourne Tennis Club.

[23] She won all 4 of her main draw matches against Great Britain, and partnered with Bollerman to defeat Tara Lumley and Georgie Willis in the deciding doubles to win the trophy for the Rest of the World.