# Xu Jiayu

Xu Jiayu (Chinese: 徐嘉余; pinyin: Xú Jiāyú; born 19 August 1995) is a Chinese competitive swimmer who specializes in the backstroke. He is the Olympic Silver medalist (2016 Rio de Janeiro and 2024 Paris) and twice consecutive world champion (2017 Budapest and 2019 Gwangju) in the 100 meters backstroke.

## Early and personal life

Xu was born in Wenzhou, Zhejiang. His mother Yu Zhenzhen (余珍珍) is a former swimmer who specialized in the butterfly. He has an elder sister Xu Si (徐思).
Xu started swimming at the age of 4 under his mother's guidance.
Xu is an alumnus of Shanghai Jiao Tong University.

## Swimming career
### Olympic Games

Xu competed for China at the 2012 Summer Olympics, and won a silver medal in the 100 metre backstroke at the 2016 Summer Olympics. He also won a silver medal in the 4x100 mixed medley at the 2020 Summer Olympics and another silver medal in the 100 metre backstroke at the 2024 Summer Olympics. He won his first gold medal in the 4 × 100 metre medley relay at the 2024 Summer Olympics.
Xu is the current national record holder in backstroke races in all distances (50, 100, and 200 metres). He held the world record in the 100 m backstroke short course from 2018 to 2020.

### International Competitions

At the 2014 Asian Games, Xu, Ning Zetao, Li Zhuhao and Li Xiang teamed up to win the men's 4 × 100 metre medley relay. Individually, Xu received silver medals in the 100m backstroke and 200m backstroke. While also receiving a bronze medal in the 50m backstroke.
At the 2016 short course World Championships, Xu won the bronze medal in the 100 metre backstroke.
At the 2017 World Aquatics Championships, Xu became the first male Chinese swimmer to win gold in the 100m backstroke in a time of 52.44 seconds. He also received the bronze medal as a part of the mixed medley relay.
At the 2018 Asian Games, Xu received six gold medals. He swept the backstroke events and was part of the Asian record setting mixed and men medley relays.
At the 2019 World Aquatics Championships, Xu successfully defended his 100m backstroke title with a time of 52.43 seconds. Xu also placed sixth in the 50m backstroke.

## Career best times
### Long course (50-meter pool)

| Event | Time | Meet | Date | Note(s) |
| 50 m backstroke | 24.38 | 2022 Hangzhou Asian Games | 25 September 2023 | NR |
| 100 m backstroke | 51.86 | 2017 Chinese Championships | 12 April 2017 | AR |
| 200 m backstroke | 1:53.99 | 2018 Asian Games | 23 August 2018 | NR |
| 4 × 200 m freestyle relay | 7:04.74 | 2019 World Aquatics Championships | 26 July 2019 | NR |
| 4 × 100 m medley relay | 3:27.01 | 2022 Hangzhou Asian Games | 26 September 2023 | AR |
| 4 × 100 m mixed medley relay | 3:38.41 | 2020 Chinese Championships | 1 October 2020 | WR |

### Short course (25-meter pool)

| Event | Time | Meet | Date | Note(s) |
| 50 m backstroke | 22.70 | 2018 FINA Swimming World Cup | 3 November 2018 | AR |
| 100 m backstroke | 48.88 | 2018 FINA Swimming World Cup | 11 November 2018 | WR |
| 200 m backstroke | 1:48.32 | 2018 FINA Swimming World Cup | 9 November 2018 | NR |
| 4 × 200 m freestyle relay | 6:47.53 | 2018 FINA World Swimming Championships | 14 December 2018 | AR |
| 4×50m medley relay | 1:33.95 | 2016 FINA World Swimming Championships | 10 December 2016 | NR |
| 4 × 100 m medley relay | 3:26.87 | 2016 FINA World Swimming Championships | 11 December 2016 | NR |
| 4×50m mixed medley relay | 1:38.69 | 2018 FINA Swimming World Cup | 4 November 2018 | NR |
Key: WR = World Record, AR = Asian Record, NR = National Record