However, as the miyatsuguchi (opening under the sleeve) of the sacred costumes at Tsuruoka-hachimangu Shrine, which is one of Japan's heritage sites from the Kamakura period, have been sewn together, some historians believe that kimono worn in the Heian period (which was prior to the Kamakura period) also had large tsutsusode.
しかし、後世鎌倉時代の遺品である鶴岡八幡宮の神宝装束は身八つ口を縫い付けていることから、「平安時代の装束も巨大な筒袖だったのではないか」と言う説がある。