He is 2.03 m (6 ft 8 in) tall and played the small forward-power forward positions. He currently serves as director of basketball operations for the German Basketball Bundesliga team Alba Berlin. Harnisch has played professional basketball for the German Basketball Bundesliga teams Gießen 46ers, Bayer Giants Leverkusen and Alba Berlin.
Because of his spectacular dunkings, Harnisch was known throughout the league as Flying Henning.
From 1990 to 1998 Harnisch won 9 German Basketball Championships in a row (7 with Leverkusen, 2 with Berlin), a record that has not been broken yet. Further, Harnisch won 5 German Bundesliga Cups (4 with Leverkusen, 1 with Berlin). He was a member of the team that won Germany"s only Gold Medal at the 1993 European Basketball Championship.
As a member of the German national basketball team, Harnisch competed at the 1992 Summer Olympics, four Eurobaskets, and one world championship.
