Most Improved National Boys 400m Marks Compared to 2025

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Improvement Rankings: Top National Boys 400m marks compared to their season’s best performances from 2025.

Most Improved - 400 Meter Dash

Comparing 2026 season to 2025 season

Rank Improved Athlete/Team Class 2025 PR 2026 PR
1 -17.78 2027 1:09.88 52.10
2 -14.95 2026 1:06.38 51.43
3 -12.14 2027 1:04.34 52.20
4 -11.58 2028 1:03.98 52.39
5 -11.46 2028 1:00.66 49.20
6 -10.53 ...