2022 Myers won the Albie Thomas 1 Mile Australian Championship on 5 December 2022, at The Crest in Sydney.
2023 Myers broke
Ryan Gregson's Australian under-18 record for the
1500 metres by more than three seconds when he ran 3:40.6 on 23 January 2023. In February 2023, Myers became the second youngest person in history to break the four-minute mile. Myers ran 3:55.44 seconds at Albert Park in Melbourne at the Maurie Plant Meet aged 16 years and 259 days. Myers was nine days older than
Jakob Ingebrigtsen when he ran 3:58.07 in May 2017, but was more than two seconds faster. Speaking about breaking the world record for a 16-year-old Myers said: "I don't think it changes much for me. It is about how you progress to the open ranks. It's only an age world record. It's cool to have, but it's not the be-all and end-all." The time also broke the Australian u-20 record. In July 2023, Myers clocked a 1500m time of 3:33.26 at the
Diamond League event in
Silesia. It was the fastest 1500m run by an U18 athlete ever, breaking the 3:33.72 set by
Nicholas Kiptanui Kemboi of Kenya in 2006. In September 2023, he acted as pacemaker for
Jakob Ingebrigtsen's European record in the mile (3:43.73) at the Diamond League final in
Eugene, Oregon.
2024 In February 2024, Myers won the men's 1500m at the Adelaide Invitational with a time of 3:34:55. This was a new meeting record, two seconds ahead of the previous record set by
Pat Scammell in 1988. On 15 February 2024, he lowered his personal best at the John Landy Mile at Melbourne's Maurie Plant Meet to 3:52.44. On 22 February, at Bankstown's the Crest athletic track, Myers set a new record for an Australian running in Australia of 3:33.30 (beating the previous record set by
Jye Edwards on 18 April 2021 at the Australian National Athletics Championships at the Sydney Olympic Park). In March 2024, he ran a new personal best and Australian U20 record time of 7:46.38 to win the Australian 3,000 metres national title in Sydney. Myers surpassed this mark at the Zatopek 10 meeting at Lakeside Stadium, Melbourne, on 14 December, where he ran 7:41.11. In May 2024, in the
Bowerman Mile at the
Prefontaine Classic, Myers set a new personal best of 3:50.15. He qualified fastest for the final of the 1500 metres at the
2024 World Athletics U20 Championships in
Lima, Peru and in the final won the silver medal behind
Abdisa Fayisa of Ethiopia.
2025 On 25 January, the Dr. Sander Invitational in New York, Myers took almost two seconds off the
world indoor under-20 mile record, running 3:53.12 at the Dr Sander Invitational. The time improved the 3:55.02 previous record set by
German Fernandez in 2009. On 2 February 2025, he set a national record of 7:33.12 over 3000 metres at the
New Balance Indoor Grand Prix. On 8 February 2025, Myers broke his world indoor under-20 mile record by over 5 seconds, running 3:47.48 in the
Wanamaker Mile at the
Millrose Games in
New York City. His time makes him the fifth fastest indoor mile runner in history, and is an Oceanian area record: both indoor and outdoor, equalling
Ollie Hoare's outdoor record). En route, Myers set a new 1500m personal best of 3:32.67, which stands as the fastest under-20 indoor 1500m of all time. He won the
Australian Athletics Championships 1500 metres title in Perth on 12 April 2025. The following day, he finished runner-up to Seth O'Donnell in the 5000 metres race at the championships. He was runner-up in the Dream Mlle in 3:48.87 at the
2025 Bislett Games, part of the
2025 Diamond League, on 12 June 2025. He ran an Oceania under-20 record of 3:29.80 for the 1500 metres at the
Golden Spike Ostrava on 24 June 2025. In September 2025, he competed at the
2025 World Championships in
Tokyo, Japan, without advancing to the semi-finals. On 28 November, Myers won the Australian World Cross Country Championships Selection Trials over 10km in 29:43 ahead of Seth O'Donnell.
2026 On 17 January, Myers ran the fastest mile ever recorded in the month of January with 3:49.81 at the Washington Preview in Seattle. It was the fastest time recorded on Australian soil, taking the all-comers record from
Hicham El Guerrouj. He lowered that record to 3:29.85 in winning the Australian Championships on 10 April in Sydney.{{cite web|title= KENNEDY AND MYERS SHINE UNDER FRIDAY NIGHT LIGHTS AT AUSTRALIAN ATHLETICS CHAMPIONSHIPS|website=Athletics.com.au|url= https://www.athletics.com.au/news/kennedy-and-myers-shine-under-friday-night-lights-at-australian-athletics-championships/ ==Personal life==