[3] On 15 July 2018 in Tampere, Zapletalová took fifth place in the 400 m hurdles at the World U20 Championships.

On 2 August 2020, she won the 400 m hurdles in Budapest with a time of 56.19 seconds, thus improving her personal best by almost seven tenths and smashing previous Slovak record.

[4] On 30 August in Trnava, Zapletalová improved by exactly one second, setting new national record in 55.19 sec.

In June 2021, at the FBK Games in Hengelo, Netherlands, she qualified for the delayed 2020 Tokyo Olympics in the 400m hurdles, running 55.29.

[5] Zapletalová took almost one second off her previous national record to win a gold medal at the European U23 Championships in July, where she clocked 54.28 sec.