Swimming warmup at Olympics can be a chaotic 'nightmare'
FILE - In this July 21, 2021, file photo, athletes exercise during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo, Japan. With hundreds of swimmers scrambling to get their warmup done at the same time, multiple athletes in each lane, everyone diving over one another and some competitors using snorkels, kickboards and other paraphernalia, warmup is organized chaos. (AP Photo/Matthias Schrader, File)

FILE - In this July 21, 2021, file photo, athletes exercise during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo, Japan. With hundreds of swimmers scrambling to get their warmup done at the same time, multiple athletes in each lane, everyone diving over one another and some competitors using snorkels, kickboards and other paraphernalia, warmup is organized chaos. (AP Photo/Matthias Schrader, File)

Jul. 23, 2021 01:12 AM EDT
FILE - In this July 21, 2021, file photo, Athletes exercise during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo, Japan. With hundreds of swimmers scrambling to get their warmup done at the same time, multiple athletes in each lane, everyone diving over one another and some competitors using snorkels, kickboards and other paraphernalia, warmup is organized chaos. (AP Photo/Matthias Schrader, File)

FILE - In this July 21, 2021, file photo, Athletes exercise during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo, Japan. With hundreds of swimmers scrambling to get their warmup done at the same time, multiple athletes in each lane, everyone diving over one another and some competitors using snorkels, kickboards and other paraphernalia, warmup is organized chaos. (AP Photo/Matthias Schrader, File)

Jul. 23, 2021 01:12 AM EDT
FILE - In this July 21, 2021, file photo, Mackenzie Horton of Australia exercises during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo, Japan. With hundreds of swimmers scrambling to get their warmup done at the same time, multiple athletes in each lane, everyone diving over one another and some competitors using snorkels, kickboards and other paraphernalia, warmup is organized chaos. (AP Photo/Matthias Schrader, File)

FILE - In this July 21, 2021, file photo, Mackenzie Horton of Australia exercises during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo, Japan. With hundreds of swimmers scrambling to get their warmup done at the same time, multiple athletes in each lane, everyone diving over one another and some competitors using snorkels, kickboards and other paraphernalia, warmup is organized chaos. (AP Photo/Matthias Schrader, File)

Jul. 23, 2021 01:12 AM EDT
FILE - In this July 21, 2021, file photo, Australia swimmers Bronte Campbell, left, and Cate Campbell waiting to exercise during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo, Japan. Campbell was a 17-year-old swimming phenomenon when she learned the dangers of warmup at major competitions the hard way. That’s what a head-on collision with Michael Phelps will do for you. (AP Photo/Martin Meissner, File)

FILE - In this July 21, 2021, file photo, Australia swimmers Bronte Campbell, left, and Cate Campbell waiting to exercise during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo, Japan. Campbell was a 17-year-old swimming phenomenon when she learned the dangers of warmup at major competitions the hard way. That’s what a head-on collision with Michael Phelps will do for you. (AP Photo/Martin Meissner, File)

Jul. 23, 2021 01:12 AM EDT
FILE - In this July 23, 2021, file photo, athletes exercise during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo, Japan. With hundreds of swimmers scrambling to get their warmup done at the same time, multiple athletes in each lane, everyone diving over one another and some competitors using snorkels, kickboards and other paraphernalia, warmup is organized chaos. (AP Photo/Martin Meissner, File)

FILE - In this July 23, 2021, file photo, athletes exercise during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo, Japan. With hundreds of swimmers scrambling to get their warmup done at the same time, multiple athletes in each lane, everyone diving over one another and some competitors using snorkels, kickboards and other paraphernalia, warmup is organized chaos. (AP Photo/Martin Meissner, File)

Jul. 23, 2021 01:12 AM EDT
FILE - In this July 22, 2021, file photo, Germany's team exercises during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo. With hundreds of swimmers scrambling to get their warmup done at the same time, multiple athletes in each lane, everyone diving over one another and some competitors using snorkels, kickboards and other paraphernalia, warmup is organized chaos. (AP Photo/Martin Meissner, File)

FILE - In this July 22, 2021, file photo, Germany's team exercises during a swimming training session at the Tokyo Aquatics Centre at the 2020 Summer Olympics in Tokyo. With hundreds of swimmers scrambling to get their warmup done at the same time, multiple athletes in each lane, everyone diving over one another and some competitors using snorkels, kickboards and other paraphernalia, warmup is organized chaos. (AP Photo/Martin Meissner, File)

Jul. 23, 2021 01:12 AM EDT