2005−2006 In 2005, Nistor was selected as a member of the Romanian senior national artistic gymnastics team. However, she was unable to compete in 2005 due to back and knee injuries. She returned to international competitions in 2006, starting at the Cottbus World Cup where she finished sixth in the beam finals. At the European Championships in
Volos, Greece, she won silver with the team and only competed on uneven bars in the apparatus events, where she finished sixth. She resumed competing in the all-around at the Romanian Championships that year where she won silver behind
Sandra Izbaşa. Steliana was also a member of the national team competing for the
2006 World Championships in
Aarhus, Denmark. According to the team's coach, Nicolae Forminte, the 2006 team was Romania's most inexperienced generation since the time of
Nadia Comăneci. Of Romania's team, only
Floarea Leonida had previous world championship experience. The Romanian team placed fourth in the team competition; the first time since 1981 that the Romanian team failed to medal at a world championship. She also placed fourth all-around behind her teammate
Sandra Izbaşa and seventh on beam and on uneven bars. She ended 2006 by pairing with
Marian Drăgulescu for the silver medal at the Swiss Cup, and by winning gold on beam and bronze on floor at the Glasgow Grand Prix.
2007 At the 16th French Internationals, Nistor placed fourth on the balance beam and 6th on the floor exercise. At Romanian Internationals, she won gold on in the all-around, on uneven bars, and balance beam, and silver in the floor exercise. At the 2007 European Championships in Amsterdam, Netherlands, Nistor placed 4th in the all-around, won silver on uneven bars, and bronze on the balance beam. This was the first time since 1998 that a Romanian gymnast (
Claudia Presecan) medalled on uneven bars at a European Championship. At the
2007 World Championships, she scored a 60.625 in the all-around and won the silver medal behind
Shawn Johnson. She also won the silver on beam behind
Nastia Liukin and placed sixth in the uneven bars finals. She also contributed considerably to the team bronze medal by receiving the highest average score on the Romanian team. Besides the European and World championships she competed at various world cup events. She won the Swiss Cup mixed pair event with
Flavius Koczi, medaled gold on bars and bronze on floor at the Glasgow Grand Prix and won gold on beam and floor and bronze on bars at the Ghent World Cup She won gold in the team event, silver on the uneven bars and after a fall, she placed 6th on beam finals. A picture of her performing on the floor exercise at these European Championships appeared on the cover of May 2008 International Gymnastics Magazine. After the European Championships, Nistor expressed a desire to possibly retire after the
2008 Beijing Olympics. At the 2008
Romanian Championships, Nistor medaled on every event, with gold in the all-around and all apparatuses except floor exercise where she won silver. She only competed on uneven bars at a dual meet in Italy at the Mediterraneo Gym Cup the following week, citing exhaustion from the Romanian Championships coinciding with her final exams. At the
2008 Beijing Olympics, Nistor competed on every event in women's artistic gymnastics. In the team event, she performed on every apparatus, contributing a particularly high score of 16.150 on uneven bars to the team score. She won the team bronze alongside her teammates on the Romanian team:
Sandra Izbaşa,
Anamaria Tămârjan,
Gabriela Drăgoi,
Andreea Grigore, and
Andreea Acatrinei. She placed 5th in the all-around and 7th on uneven bars, both behind
Ksenia Semenova. Following the Olympic games, Nistor went back home while the other gymnasts went to
Constanta for a holiday/training camp by the seaside. A few weeks later, she formally announced on television that she would be retiring. ==Retirement==