On 26 July 2026, Riley Knebes (United States) ran their 400 metres hurdles in 56.48 seconds at New York (United States Championships).
| 20.00 |
| 7.61 |
15 L |
L |
| H5 | 4.70(+0.10) | 24.70 | 7.45 | 16 R | R |
| H6 | 4.93(+0.23) | 29.63 | 7.10 | 16 L | L |
| H7 | 5.12(+0.19) | 34.75 | 6.84 | 17 L | L |
| H8 | 5.33(+0.21) | 40.08 | 6.57 | 17 L | L |
| H9 | 5.18(-0.15) | 45.26 | 6.76 | — — | — |
| H10 | 5.24(+0.06) | 50.50 | 6.68 | — L | L |
| Finish | 5.98 | 56.48 | 6.69 | — — | — |
Avg. interval
4.89s
Std. deviation
0.33
Deceleration
Stride pattern
Fastest interval: 4.34s (H2–H3).
Excellent fatigue resistance: only 9.7% speed loss between the first and second halves (7.49 → 6.77 m/s).
Lead leg alternation: 8× Left, 1× Right.
Max speed
8.06m/s
Avg speed
7.08m/s
Std. deviation
0.33s