, meaning "way of the jà Â", or , meaning "art of the jà Â", is a Japanese martial art using a short staff called jà Â. The art is similar to bà Âjutsu, and is strongly focused upon defense against the Japanese sword. The jà  is a short staff, usually about 3 to 5 feet (0.9 to 1.5 m) long.
Shintà  Musà Â-ryà « jà Âjutsu (sometimes known as Shintà  Musà Â-ryà « jà Âdà  - "Shindà Â" is also a valid pronunciation for the leading characters) is reputed to have been invented by the great swordsman Musà  Gonnosuke Katsuyoshi (夢æ³ æ¬Âä¹Âå© Ã¥ÂÂÃ¥ÂÂ, fl. c.1605, date of death unknown) about 400 years ago, after a bout won by the famous Miyamoto Musashi (å®®æ¬ æ¦èµ, 1584–1645). According to this tradition, Gonnosuke challenged Musashi using a bà Â, or long staff, a weapon he was said to wield with great skill. Although other accounts of this first duel disagree, according to the oral tradition of Shintà  Musà Â-ryà «, Musashi caught Gonnosuke's bà  in a two-sword "X" block (jà «ji-dome; Ã¥ÂÂÃ¥ÂÂæ¢ãÂÂ). Once in this position, Gonnosuke could not move in such a way as to prevent Musashi from delivering a counterattack, and Musashi elected to spare his life.
Gonnosuke's wanderings then brought him to Mount Hà Âman in Chikuzen (modern-day Fukuoka) where, after a period of purification, meditation, and training, Gonnosuke claimed to have received a divine vision from a small child who told him: "holding a round stick, know the solar plexus" ("maruki wo motte, suigetsu wo shire"ãÂÂ丸æ¨ãÂÂ以ã£ã¦ãÂÂæ°´æÂÂãÂÂçÂ¥ãÂÂãÂÂ). By shortening the length of the bà  from roughly (or, in Japanese measurement units, four shaku, two sun and one bu), he could increase the versatility of the weapon, giving him the ability to use techniques created for the long staff, spear fighting and swordsmanship. The length of the new weapon was longer than the tachi (long sword) of the period, but short enough to allow the reversal of the striking end of the jà  in much tighter quarters than the longer bà Â. Gonnosuke could alter the techniques he used with the jà  stick, depending on the opponent he faced, to provide himself with many different options of attack. He named his style Shintà  Musà Â-ryà « and challenged Musashi again. This time, when Musashi attempted to use the jà «ji-dome block on the jà  staff, Gonnosuke was able to wheel around the other end of the staff (because of the reduced length), forcing Musashi into a position where he had to concede defeat. Returning the courtesy he received during their previous duel, Gonnosuke spared Musashi's life.
This may be an embellished story of the creation of jà Âjutsu, as the oral tradition of Shintà  Musà Â-ryà « is the only mention of this second duel, or for that matter, a person defeating Musashi in combat. Witness accounts of Musashi's life, as well as his own writings, insist he retired from dueling undefeated. Furthermore, while this legend is the most well-known tale to include the use of the jà Â, Gonnosuke cannot be credited as the sole creator of the jà  as a number of other schools from the same period and with no links to Shintà  Musà Â-ryà « also include jà Âjutsu in their curriculum (Suià Â-ryà «, Tendà Â-ryà «, Hà Âten-ryà «, Takenouchi-ryà «). What is known about Gonnosuke after his alleged second duel is that he eventually became the martial arts instructor for the Kuroda clan of northern Kyà «shà «, where jà Âjutsu remained an exclusive art of the clan until the early 1900s, when the art form was taught to the general public.
The modern study of jà Âdà  has two branches.
One is koryà «, or "old school" jà Âdà Â. This branch is further subdivided into a number of different schools which include jà Âdà  or jà Âjutsu in their curriculum (Shintà  Musà Â-ryà «, Suià Â-ryà «, Tendà Â-ryà «, Hà Âten-ryà «, Kukishin-ryà «, Takenouchi-ryà «, etc.). These schools also teach the use of other weapons such as the sword, the naginata, the short staff (tanjà Â), the chained sickle (kusarigama), the truncheon (jutte), and jà «jutsu (close combat for defeating an opponent in which one uses either a short weapon or none). Most practitioners specialise in only one school.
The other branch is called Seitei Jà Âdà  and is practiced by the All Japan Kendà  Federation (å ¨æÂ¥æΣéÂÂé£ç Zen Nippon Kendà  Renmei). Seitei is a simpler form of jà Âdà Â, compared to the Koryà « styles, with only 12 pre-arranged forms (kata), compared to Shintà  Musà Â-ryà « for instance, which has 64 In addition to these 12 kata the student will also study their koryà «.
Jà Âjutsu has also been adapted for use in the Japanese police force, who refer to the art as keijà Â-jutsu (è¦æÂÂè¡Â), or police stick art.
Aiki-jà  is the name given to the set of martial art techniques practiced with a jà  according to the principles of aikido, taught first by Morihei Ueshiba then further developed by Morihiro Saito, one of Ueshiba's most prominent students.