Two men in swimsuits jumped into the pool to assist the team, which was helping Kobayashi to the side. The other team members climbed out to await their scores, while the ailing woman clung to the pool's edge.
Kobayashi was lifted out by the two men in swimsuits and she buckled to her knees. Her body and head went limp as they carried her. She was wrapped in a white sheet and rushed away on the stretcher, attended to by several volunteers and medical personnel.
The woman hyperventilated because of stress, said Hiroshi Takeuchi, press officer for the Japanese team.
"That kind of thing has happened to her before. She is a very nervous athlete," he said. "She is good. Don't worry, she's not in serious condition."
Kobayashi was conscious and resting at the arena, and did not require a hospital visit, he said.
The Japanese team tied the United States for fifth in the final. Japan was assessed a two-point penalty for touching the bottom of the pool during its routine.
