On 26 July 2026, Chloe Fair (United States) ran their 400 metres hurdles in 56.59 seconds at New York (United States Championships).
| 19.65 |
| 7.69 |
16 L |
L |
| H5 | 4.60(+0.05) | 24.25 | 7.61 | 16 R | R |
| H6 | 4.80(+0.20) | 29.05 | 7.29 | 16 L | L |
| H7 | 5.07(+0.27) | 34.12 | 6.90 | 16 R | R |
| H8 | 5.19(+0.12) | 39.31 | 6.74 | 17 R | R |
| H9 | 5.33(+0.14) | 44.64 | 6.57 | 18 L | L |
| H10 | 5.42(+0.09) | 50.06 | 6.46 | 18 R | R |
| Finish | 6.53 | 56.59 | 6.13 | — — | — |
Avg. interval
4.83s
Std. deviation
0.42
Deceleration
Stride pattern
Fastest interval: 4.21s (H2–H3).
Deceleration of 12.9% between the first half (7.63 m/s) and the second half (6.65 m/s).
Steady stride pattern.
Lead leg alternation: 4× Left, 6× Right.
Max speed
8.31m/s
Avg speed
7.07m/s
Std. deviation
0.42s