The Japanese researcher who gave his name to the 20-seconds-on, 10-seconds-off interval protocol is Izumi Tabata.
Tabata studied high-intensity exercise while working with Japan’s speed-skating program and researchers at the National Institute of Fitness and Sports in Tokyo. A 1996 study compared repeated bursts of extremely intense cycling with longer, steady-state exercise. The interval group worked for 20 seconds, rested for 10 seconds, and repeated the pattern for four minutes, or eight cycles.
The method became known as the Tabata Protocol, although Tabata has credited Olympic speed-skating coach Koichi Irisawa with pioneering the training format. The original study used highly trained athletes and effort levels far beyond a casual workout, so many modern “Tabata” classes are adaptations rather than exact reproductions.
A common mix-up is treating all HIIT as Tabata. HIIT is the broader category; Tabata refers specifically to the famous 20:10 structure associated with Tabata’s research.