Shimizu was born in 1940 in Fukuoka, Japan. He had been training judo since childhood and held a 4th dan in this art when he changed to aikido in 1963. He then became one of the last personal students of the aikido founder Morihei Ueshiba. After Ueshiba died in 1969, Shimizu, then with a 7th dan in aikido, founded his own school in Tōkyō named Tendoryu (School of the Way of Heaven).
Tendoryu Aikido is characterized by its large and clear movements, emphasizing naturalness and harmonic flow of motion.
Shimizu received the 'Foreign Minister Award', an award from the Foreign Minister of Japan, on July 16, 2002 for his work spreading aikido abroad. Shimizu-sensei was the first Aikido and Budo artist to receive this award. In the same year he was invited to the autumn garden party at the imperial palace in Akasaka, Tōkyō.
- Suenaka, Roy; Watson, Christopher (1997-11-15). Complete aikido: aikido kyohan : the definitive guide to the way of harmony. Tuttle Publishing. pp. 37–. ISBN 978-0-8048-3140-6. Retrieved 21 June 2011. CS1 maint: discouraged parameter (link)
- Moriyama, Y. "Shimizu Sensei". About Tendo-ryu. Tendo-kan. Retrieved 18 March 2013. CS1 maint: discouraged parameter (link)
- Shimizu, Kenji - translated by Birgit Lauenstein and Peter Nawrot. "The Garden Party". Kawaraban No. 53. Tendoryu Aikido Berlin (TAB) e.V. Archived from the original on 27 December 2012. Retrieved 18 March 2013. CS1 maint: discouraged parameter (link)
- Tendokan Tokyo / Japan Tendokan Tokyo / Japan
- Tendoryu Aikido Federation Germany Tendoryu Aikido Federation Germany
- Tendoryu Aikido Berlin e.V. Tendoryu Aikido Berlin e.V. - translation from the articles written by Kenji Shimizu sensei.
- Aikido Berlin-Süd e.V. Tendoryu Aikido in Berlin Steglitz
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