Dziamidava represented Belarus at the 2012 Summer Olympics in London, where she qualified for the women's 4 × 100 m freestyle relay, along with her teammates Yuliya Khitraya, Sviatlana Khakhlova, and double Olympic silver medalist Aliaksandra Herasimenia. Swimming the third leg, Dziamidava posted her time of 55.94 seconds, and the Belarusian team went on to finish the first heat in seventh place and thirteenth overall, setting a new national record time of 3:40.67.