What is a judo coach allowed to do during a contest?

• One coach may accompany the athlete, and must remain seated in the coach's chair throughout the contest. The coach cannot be swapped for another during it.
• When coaching is allowed: only in the pause after "mate" and before "hajime", and only as tactical advice, encouragement and instruction to the coach's own athlete.
• First offence: a warning. A repeat: exclusion from the competition area for the rest of the day.
• A coach may not have a communication device during the contest.
• A coach who coaches from the stands has the accreditation withdrawn and is put out of the hall.
• The coach is never allowed on the mat, even when the athlete is being treated.
• A coach who arrives late at judogi control may not accompany the athlete. An athlete whose judogi fails the control fights without a coach in the chair.
• There is a dress code: a national tracksuit in the preliminaries and a formal suit for the final block.
• A coach who wants a decision looked at may apply afterwards to review that one action on video.

The contest is between two athletes. Limiting coaching to the pauses keeps a second voice out of the fighting, and keeps the noise at the mat-side from reaching the referee.