Judo has been an Olympic sport since 1964 for men (with only one interruption in 1968) and since 1992 for women. World championships for men have been organized since 1956 and for women since 1980. Since 1987, the championships have been organized every two years and are mixed.
The competition area is padded with tatami and must have a minimum size of 14 x 14 meters. Matches occur in an 8 x 8 meters to 10 x 10 meters inner area, while the outer space is a safety zone.
There must be at least a 3 meters safety zone between competition areas (if they are side by side).
The main objective is to get an ippon, which consists in projecting the opponent in such a way that he touches his back on the ground or by immobilizing him for more than 25 seconds.
One competitor is designed to wear a blue uniform while the other wears a white one.
There are several degrees of scores:
- Koka – Lowest score. Represents 1/4 point. Occurs
when the opponent falls sitting down. Koka is not cumulative.
- Yuko – 1/3 point. When the opponent falls sideways.
It is not cumulative.
- Wazari – 1/2 point. It is cumulative. A second
wazari is an ippon and ends the fight. Wazari is an ippon not completed
- Ossaekomi – When the fight is carried out on the
ground. Once the opponent is immobilized, a counting starts.
10 to 15 seconds: koka 15 to 20 seconds: yuko 20 to 25 seconds: wazari More than 25 seconds: ippon
- Ippon – The perfect point which ends the fight. The opponent falls touching his back on the ground.
Penalties (shido) also exist and give points to the oponent:
|1 shido – koka|
|2 shidos – yuko|
|3 shidos – wazari|
|4 shidos – ippon by hansokumake (disqualification)|
- Sogo gachi – Composed victory. A competitor scores
a wazari and his opponent is later punished with three shidos.
- Golden Score – When the number of points and penalties
are equal, the score and the timer are reset, and the fight restarts.
The winner will be the one who scores the first point or who benefits
from the first penalty of the opponent.
- Hantei – If equality still persists, the referees decide who the winner is.
Olympic Weight Categories (as for 2008)
|Extra Lightweight||Half Lightweight||Lightweight||Half Middleweight||Middleweight||Half Heavyweight||Heavyweight|
|Men||-60 kg||60-66 kg||66-73 kg||73-81 kg||81-90 kg||90-100 kg||+100 kg|
|Women||-48 kg||48-52 kg||52-57 kg||57-63 kg||63-70 kg||70-78 kg||+78 kg|