Dan (rank) highest level that might be attained, with instructor certification and judge/judgment authorization being understood as higher-level or more sophisticated. Many arts use between one and ten dan ranks: In some martial arts, black belts are worn for all "dan" grades. In others, the highest grade (10th "dan") wears a red colored belt. In Jūdo and Shotokan 6th to 8th "dan" may wear a red and white-patterned belt and 9th to 10th "dan" may wear a solid red belt. There is some variation even within styles. Generally, belts do not have markings that indicate the actual "dan" grade. Okinawan styles used
Judo in Canada 1989. A third article, "Physical performance attributes of junior and senior women, juvenile, junior, and senior men judokas", presents the results of a study of the 1989 Alberta Judo Team and was published by N.G. Little in "The Journal of Sports Medicine and Physical Fitness" in 1991. Kinesiologist, 1993 Canadian Champion (-65 kg category), and former member of the Canadian Judo team Wayland Pulkkinen self-published "The Sport Science of Elite Judo Athletes: a Review & Application for Training" in 2001. Two undated articles derived from the book are available on the website "JudoInfo.com". Other authors have focused on the social