On 28 June 2026, Bianca Stubler (United States) ran their 400 metres hurdles in 55.34 seconds at Medellín (PANAM Championships).
| 19.91 |
| 7.90 |
15 R |
R |
| H5 | 4.55(+0.12) | 24.46 | 7.69 | 15 R | R |
| H6 | 4.78(+0.23) | 29.24 | 7.32 | 15 R | R |
| H7 | 4.91(+0.13) | 34.15 | 7.13 | — — | — |
| H8 | 5.20(+0.29) | 39.35 | 6.73 | — R | R |
| H9 | 5.17(-0.03) | 44.52 | 6.77 | 16 L | L |
| H10 | 5.18(+0.01) | 49.70 | 6.76 | 16 R | R |
| Finish | 5.64 | 55.34 | 7.09 | — — | — |
Avg. interval
4.77s
Std. deviation
0.34
Deceleration
Stride pattern
Fastest interval: 4.33s (H2–H3).
Excellent fatigue resistance: only 7.9% speed loss between the first and second halves (7.56 → 6.96 m/s).
Lead leg alternation: 1× Left, 8× Right.