The 400 Is a Sprint

The 400m is a sprint; the 800 is the hybrid. And although speed training for the 400m seems counterintuitive, it should be the priority.

Van Niekerk betters 400m world record

How to quickly recover from a 400 meter sprint - Quora

One-Lap Wonders: Here are Your 400 Meter Runners for Team USA - Women's Running

World Athletics: Allyson Felix of USA Wins Gold in Women's 400m Sprint

Canandaigua's Ajavon dashes to sprint trifecta

Strategy: How to Run the 400m

Could a runner win Olympic gold medals in the 400-meter, 800-meter, and the 1,500-meter races? - Quora

Sydney McLaughlin-Levrone Picks the 400 Meters for Worlds

What's A Good 400m Time? Average 400 Meter Times By Age + Sex

The Trackwired 400 Meter Dash program was designed by elite coaches for athletes of all skill levels. Train over 8/12/16/20 week cycles. $24.99-$39.99

400 Meter Dash

Sydney McLaughlin shatters 400 hurdles record with 50.68