Izawa has chaired organizations including the World Music Festival of Peace, the Yomiuri Giants Fan Appreciation Day, and the Tokyo International Marathon.
Tokyo | ATP International Series | International Monetary Fund | International Red Cross and Red Crescent Movement | ATP International Series Gold | International Space Station | Amnesty International | International Olympic Committee | BirdLife International | International Finance Corporation | International Organization for Standardization | marathon | International Telecommunication Union | International Criminal Court | One Day International | International Nonproprietary Name | International Labour Organization | International Civil Aviation Organization | International Boxing Federation | Toronto International Film Festival | International Atomic Energy Agency | International Maritime Organization | International Development Association | John F. Kennedy International Airport | Boston Marathon | University of Tokyo | Los Angeles International Airport | International Bank for Reconstruction and Development | London Marathon | International Court of Justice |
He was very successful on the Japanese road racing circuit, winning the Tokyo International Marathon and Lake Biwa Marathon in both 1963 and 1964, and registering four wins at the Beppu-Ōita Marathon between 1967 and 1973.
Outside of his Olympic medal, his achievements include wins at the Beppu-Ōita Marathon and the Tokyo International Marathon.