The Art of 400m Pacing
How the world's best athletes pace the 400m.
The Differential: Key to Performance
The 400m is defined by the differential — the time difference between the first 200m and second 200m. Elite men average 1.3-1.9s differential, while elite women average 1.5-2.5s. A smaller differential indicates better speed endurance and more disciplined pacing.
Even pacing (reference): Michael Johnson's 43.18 from Seville (1999) is the classic tight line — only a 0.74s differential between 200m halves (21.22 + 21.96). Current world record: Wayde van Niekerk's 43.03 in Rio (2016) is faster overall with a larger +1.87s differential — more front-loaded, then holding on — showing record pace does not require the smallest split gap. For contrast, Kirani James' 43.76 Olympic win carried a 2.54s differential: explosive start, pronounced fade.
Two Schools of Pacing
Elite 400m mixes even pacing (Johnson, Reynolds) with front-loaded WR attempts (van Niekerk): you can break the record with a bigger differential if your peak speed and speed endurance align. Slower differentials are not always slower clocks — they reflect how evenly the athlete trades energy across the lap.
The Final 100m
Regardless of strategy, every 400m runner slows in the final 100m. The fastest segment is almost always 100-200m (the "free speed" portion after acceleration, before significant fatigue). The 300-400m segment accounts for 26-29% of total race time depending on performance level — a higher percentage indicates greater fatigue-induced deceleration.