Hempel made his Olympic debut at age 17 in Seoul. Hempel placed fifth.
1992
Hempel returned to the Olympics in Barcelona, but again did not medal, placing fourth.
1996
was charm, as Hempel won silver in the 10 m platform, scoring 663.27. He saved his toughest dive for last. He nailed the back 1½ somersault with 4½ twists from the free position, earning 92.88 points. It was one of the two dives out of the 72 in the finals with a 3.6 degree of difficulty.
2000
In the inaugural men's 10 m synchronized platform event, Hempel, now 29, with partner Heiko Meyer won the bronze medal at the Sydney 2000 Games, earning Hempel his second medal in four Olympic appearances. Meyer and first-time Olympian Heiko Meyer began training together in 1998 and won the bronze medal at the World Championships later that year. The pair also won the event at the 1999 European Championships. Despite these achievements, Hempel came into the 2000 Games with modest expectations. Hempel stated, "If you had asked us before the competition, we wouldn't have thought we were a chance for a medal." However, the team pulled off a solid performance on the program's most difficult dive, a back 3½ somersault tuck and reverse 3½ somersault tuck, scoring 78.54. Hempel continued, "It has the most risk but it paid off for us."
In the European Diving Championships, Hempel had an illustrious career winning silver in 1987 in Strasbourg, France, bronze in 1989 in Bonn, Germany, gold in 1993 in Sheffield, Great Britain, and silver in 1995 in Vienna, Austria. In 1997 in Seville, Spain Hempel finally won a European highboard diving gold 10 years after taking the first of three silvers on the 10-meter board. Hempel had been suffering from influenza for three days and considered pulling out of the competition. But he decided against it and was rewarded with the gold. "I'm happy it worked out at the sixth attempt," said Hempel. During the competition, he scored a rare perfect 10 mark. After taking the silver in 1987, 1989 and 1995 and bronze in 1993, he had finally added a highboard gold to the European three-meter springboard gold he won in 1993. At the 2003 Arena Diving Champions Cup in Stockholm, Hempel, now 32, was described as the man "who wrote diving history," citing the second best dive of all time in the Diving Champions Cup 3m finals performing a back 1½ somersault with 3½ twists in Vienna 1993, for a fantastic 87.36 points.
Synchronized diving
With Meyer, the synchronized pair continued to compete in the event at the World Championships, through at least 2001. They also competed separately on the men's 10 m platform. Hempel placed 4th at the 2001 Goodwill Games.
