Tomozuna stable
As a child he played baseball. Kaidō went to Meiji Nakano High School where he was a year senior of Tochiazuma, and he was named the High School Yokozuna in 1990. He was an amateur sumo champion at Chuo University before making his professional debut in March 1998, at the bottom of the third highest "makushita" division as a "makushita tsukedashi" entrant. He initially fought under the "shikona" of Tanaka, before changing to Kaito and then Kaidō (the character "Kai" being a common one in his stable or "heya)." He never made the top "makuuchi" division, but he spent 11 tournaments in the second highest "jūryō" division, which he first reached in 2003, reaching a high of "jūryō" 4. He was demoted to "makushita" in May 2005 and never made his way back. For many years he was a training partner to Sentoryū, as the two were the second and third most senior members of Tomozuna stable behind longtime "ōzeki" Kaiō. Kaidō served as Kaiō's "tsukebito" or personal assistant when he was in the lower ranks and credited his senior stablemate for encouraging him when he was struggling with injuries.