In 2015, Lada Vondrová took part in a major international event for the first time, the U18 World Championships in Cali , where it reached the semifinals over 400 meter hurdles. A year later she reached the semi-finals again at the U18 European Championships, which were held for the first time in Tbilisi , but could no longer start there. At the U20 World Championships in Bydgoszcz , Poland , she reached seventh place with the Czech 4 x 400 meter relay. In 2017 she qualified for the U20 European Championships in Grosseto , where she finished seventh in the final. In 2018 Vondrová qualified over 400 meters for the World Indoor Championships in Birmingham and made it to the semi-finals there, where she was eliminated with 53.32 seconds. With the Czech season, however, she was eliminated with 3: 34.90 minutes in advance. In the 400-meter run she qualified during the outdoor season for the European Championships in Berlin , where she was eliminated with 53.21 s in the first round, as well as at the European Indoor Championships the following year in Glasgow, Scotland, with 53.29 s. At the U23 European Championships in Gävle , Sweden , she won the silver medal over 400 meters behind Polish Natalia Kaczmarek in 52.34 s and in the hurdles she was sixth after 57.29 s. She then won the silver medal in the mixed 4 x 400 meter relay at the European Games in Minsk in 2: 17.53 minutes. Over 400 meters she qualified for the World Championships in Doha in autumn, where she reached the semifinals and was eliminated there with 52.25 seconds. In addition, she started in the mixed relay, but could not qualify for the final with 3: 18.01 min .
In 2019 Vondrová became the Czech champion in the 400-meter run outdoors and in 2019 and 2020 also indoors. In addition, she became indoor champion in the 200-meter run in 2020 .
Personal best
200 meters: 23.40 s (+0.5 m / s), July 18, 2020 in Kladno
200 meters (hall): 23.71 s, January 28, 2020 in Prague
400 meters: 51.35 s on July 4, 2020 in Prague
400 meters (hall): 51.82 s, February 23, 2020 in Ostrava