MileSplit Staff Apr 17, 2026 PRO See the rest of this article Access the complete article with MileSplit PRO. Subscribe to keep reading Already a subscriber? Log in. Improvement Rankings: Top Massachusetts 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 -9.29 Amir Bridges Cristo Rey 2028 1:14.02 1:04.73 2 -8.97 Jabari Sauveur South Shore Vocational Technical High School 2028 1:06.00 57.03 3 -8.28 William Vial Xaverian Brothers 2028 1:08.54 1:00.26 4 -7.67 Ethan Napolitano Acton-Boxborough High School 2027 1:04.90 57.23 5 -7.34 William Hutchinson Franklin County Tech School 2028 1:07.44 1:00.10 6 ...