Most Improved Iowa Boys 400m Marks Compared to 2025

Apr 24, 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	-20.64	Karsen Johnson Clarinda High School	2027	1:40.44	1:19.80
2	-15.12	Blaise Echevarria Southwest Valley High School	2028	1:21.71	1:06.59
3	-11.82	Nolan Randall H-L-V High School	2028	1:16.07	1:04.25
4	-10.79	Aiden Carter Centerville High School	2028	1:13.80	1:03.01
5	-10.41	Spencer Goettemoeller Mount Ayr High School	2028	1:23.68	1:13.27
6	-9.91