UPDATED: Freediver Kathryn Nevatt smashed the world record for swimming underwater on a single breath by 4 meters in Masterton this morning - reaching 164m.
But her effort was disqualified by judges because she was believed to have lost consciousness during the swim.
Judges upheld the decision this afternoon despite a protest from Nevatt.
Losing consciousness was shown by dipping her head as she swam underwater, judges said.
Nevatt lodged a protest against the disqualification, which was heard at 2pm today, but the judges were not swayed after viewing the video.
Nevatt swam more than six lengths of the Genesis Recreation Centre pool this morning in her third attempt, breaking the previous record of 160m.
She will have a rest day on Monday and attempt the record again on Tuesday.