Most Improved Iowa Boys 400m Marks Compared to 2025

May 29, 2026

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Improvement Rankings: Top Iowa 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	-21.53	Carter Davis Central Decatur High School	2028	1:20.44	58.91
2	-20.64	Karsen Johnson Clarinda High School	2027	1:40.44	1:19.80
3	-15.12	Blaise Echevarria Southwest Valley High School	2028	1:21.71	1:06.59
4	-12.81	Tucker Jantzon Thomas Jefferson High School	2027	1:14.00	1:01.19
5	-12.48	Aiden Carter Centerville High School	2028	1:13.80	1:01.32
6