At the 1996 Summer Olympics, Bruck was a member of the 4x100-meter medley relay team – freestyler Bruck, breaststroker Vadim Alexeev, backstroker Eithan Urbach, and butterfly specialist Dan Kutler – that made the final after placing fourth in their preliminary heat (3:42.24). The Israeli team then finished eighth in the final (3:42.90); it was the first time Israel was represented in an Olympic swimming final.
At the 2000 Summer Olympics in Sydney, Bruck helped break the national record in the 4x100m freestyle. The Israeli team swam 3:22.06 in the preliminaries, but did not advance to the finals; they officially placed 14th. Bruck also swam in the 4x100m medley relay. Israel finished fifth in the preliminary heat (3:43.39), and did not advance; they were 17th overall. In individual events, Bruck placed 38th in the 100m freestyle (51.62), and 34th place in the 50m freestyle (23.21).
Bruck attended Auburn University from 1991-1994 and received 18 All-America honors, including a school-record of 7 in 1994. Bruck helped Auburn remain one of the top swimming teams in the country. In 1992-1993, the Tigers finished sixth in the team competition at the NCAA Championships and the following year, they finished fourth. In 2001, Bruck was inducted into Auburn's Wall of Fame.
While at Auburn, Bruck steadily climbed through the world rankings in the freestyle sprinting events. In two short years following the 1992 Summer Olympics, he jumped from 96th to 15th in the world in the 50 metres and from 123rd to 30th in the 100 metres.
After graduating in 1994, Bruck continued his international success while representing Israel. At the 1994 World Aquatics Championships in Rome, Italy, Bruck finished eighth in the 50m freestyle (22.84), and eighteenth in the 100m (50.81). In 1995, he finished in sixth place in the 50-meter freestyle at the European Championships in Vienna. His time of 22.79 broke the Israeli national record.
In 1997, Bruck finished seventh in the 50m freestyle (23.03) at the European Championships in Seville, Spain, and won the 50m freestyle and 100m freestyle at the Maccabiah Games. That year, he shared Israel's Sportsman of the Year honors with colleague-swimmer Eithan Urbach.
At the 2000 European Championships, Bruck was a member of the 4x100-meter medley (3:43.48) team which placed eighth.