 Ramba uchinyora ndima iyi - Saito akatanga judo kuchikoro chesekondari, uye muna 1974, akaongororwa kuti aendeswe kuKokushikan Junior High School, iri muSetagaya, Tokyo. Akaenderera mberi nekudzidzira judo pachikoro chepamusoro cheKokushikan, uye akahwina makwikwi eboka repakati pechikoro chepamusoro judo panguva yegore rake rekutanga. Akapinda Kokushikan University muna 1979, uye akatarisana naYasuhiro Yamashita kanokwana ka7 mumakwikwi ekupedzisira eAll-Japan Judo Championships, Jigoro Kano Cup, uye All-Japan University Judo Championships. Akarasikirwa naYamashita mumakwikwi ose ekupedzisira, asi akaenzana naye kakawanda panguva yemimwe mitambo. Saito akaramba achishanda paKokushikan University mushure mekupedza kudzidza muna 1983, uye akahwina menduru yegoridhe muchikamu cheheavyweight 95 kg ye1984 Summer Olympics uye muchikamu chehuremu hwakavhurika hwe1983 World Judo Championships.. Muna 1985 World Judo Championships, akatarisana naCho Yong-Chul weSouth Korea uye akamanikidzwa kurega kubva mumutambo mushure mekunge ruoko rwake rwabviswa nekumira kwakarongedzwa naCho. Akakuvarawo ibvi rake rerudyi pamberi peAll-Japan Championships muna 1987, asi akadzoka pa1988 All-Japan Championships, achikunda mukwikwidzi kekutanga kuti awane rwendo rwake rwechipiri kumitambo yeOlympic. Saito akatarisana naCho Yong-Chul zvakare mumasemi-fainari e1988 Summer Olympics, achikwikwidza pasi pekumanikidzwa kwakanyanya mushure mekunge vamwe vese maJudooka eJapan mu1988 Olimpiki vakundwa vasati vasvika kumagumo. Akakunda Cho nesarudzo, uye akakunda mukupedzisira Henry Stöhr kuti atore menduru yake yechipiri yegoridhe yeOlympic. 