Jan assumed position of the National Performance Director in April 1998. He contributed to Pentathlon GB winning 4 Olympic Medals in 2000, 2004 and 2008 Olympic Games, establishing of the National Training Centre at the University of Bath and implementing of the Performance Pathway System in Modern Pentathlon in the UK. Currently he is one of the longest serving Performance Directors in British Sport.
From 1986 to 1990 he was the Technical Director of the Czechoslovakian Pentathlon. From 1990 to 1994 Jan was the Head Coach of the Mexican National Teams and from 1995 to 1997 Head Coach of the US Pentathlon Association.
Jan has represented his native Czechoslovakia in Modern Pentathlon winning the individual Bronze and team Silver medals in 1976 Olympic Games in Montreal.