Born in Budapest,[3] she won her first continental medal at the 1975 European Athletics Junior Championships at the age of seventeen, coming third in the 100 m hurdles.[4] She joined Vasas SC, a major sports club in Budapest.[3] In 1978 she won her first senior national titles at the Hungarian championships, winning the 60 metres hurdles indoor title then the 100 m hurdles title outdoors.[5][6] The 1978 European Athletics Championships was the venue of her major international debut and she reached the semi-final stage, running a time of 13.36 seconds.[7]
Siska defended her Hungarian 60 m hurdles title in 1979 – she would go undefeated in this competition until 1982.[5] This led to her selection for the 1979 European Athletics Indoor Championships and she was again a semi-finalist at continental level.[8] Outdoors, she was bested by pentathlete Margit Papp in the 100 m hurdles at the Hungarian Championships.[6] She returned to the top of the national scene in 1980 and ran a personal best time of 13.17 seconds, ranking in the top-25 hurdlers that year.[9] Her Olympic debut followed, as she was chosen to compete for Hungary at the 1980 Summer Olympics in Moscow. She did not reach the final, falling in the semi-final and failing to finish the race.[3]
She finally reached a senior final at the 1981 European Athletics Indoor Championships, where she placed sixth in the 50 metres hurdles after running a best of 6.89 seconds in the qualifiers.[8] After winning her fifth and final 60 m hurdles national title,[5] she was entered into the 1982 European Athletics Indoor Championships, but did not progress to the final.[8] She continued to improve as an athlete outdoors, winning the 1983 national title in a championship record time 13.20 seconds.[6] The inaugural 1983 World Championships in Athletics marked her second appearance on the global stage and she reached the semi-finals of the 100 m hurdles.[10]
Her breakthrough in the 100 m hurdles event came in 1984: at the age of 26 she set a Hungarian record of 12.76 seconds in Budapest. This time placed her eleventh on the global rankings for the season.[9] She won a national title in the 100 metres, though her winning time over twelve seconds was the slowest to win the event for over two decades.[6] With the Eastern Bloc nations boycotting the 1984 Los Angeles Olympics, she competed at the Friendship Games instead and place eighth.[11] For her performances she was selected as the female Hungarian Athlete of the Year by the national federation.[12] The greatest achievement of her career followed at the 1985 IAAF World Indoor Games. At the event (a precursor to the modern IAAF World Indoor Championships) she set a lifetime best of eight seconds flat for the 60 m hurdles in qualifying then went on to take the gold medal in the final.[13] Outdoors she had a season's best of 12.99 seconds, enough to place in the top twenty for the year.[9]
In 1986 she set the Hungarian Championships record at 12.92 seconds – a mark which remains undefeated.[6] She came close to her personal best in Budapest in August, running 12.77 seconds to finish eleventh on the world season's rankings.[9] The standard of competition was high at the 1986 European Athletics Championships; in spite of running 12.90 in the semi-finals, this was only enough for fifth in the race which was won by Yordanka Donkova, who broke the world record that year.[7] After the competition, Siska topped the podium at the Athletissima meeting in Lausanne with a run of 12.86 seconds.[8]
Her 1987 season was highlighted by a run of 12.77 seconds in Budapest, which placed her seventh in the world rankings for the season.[9] This marked the last time that she featured near the top of the rankings. In 1988 she won an eighth Hungarian 100 m hurdles – the last national title of her career.[6]
