Six-day world best
Covered 1,036.800 km at the Colac Six Day Race in Australia, the world best until Matthieu Bonne’s 1,045.519 km in 2024; the IAU still lists it as the men’s 45–49 six-day best.
Athlete profile · Sources reviewed Oct 20, 2026
Yiannis Kouros
Credited by the IAU with more than 160 world records
Yiannis Kouros is a Greek ultrarunning pioneer whose career included more than 160 world-record performances and landmark marks from 24 hours to 1,000 miles.
GreeceM70–74
The record so far
Yiannis Kouros is a Greek ultrarunning pioneer whose performances helped define modern fixed-time and multiday racing. The International Association of Ultrarunners credits him with breaking more than 160 world records across distances and time limits.
His landmark results include 303.506 km in 24 hours, 473.495 km in 48 hours, 1,036.800 km in six days, and 1,000 miles in 10 days, 10 hours, 30 minutes, and 36 seconds. Later athletes have surpassed his former 24-hour, 48-hour, and six-day world bests: Aleksandr Sorokin ran 319.614 km in 24 hours in 2022, and Matthieu Bonne covered 1,045.519 km in six days in 2024 and 485.099 km in 48 hours in 2025. The historical significance of those performances remains central to the sport.
Kouros also won the first Spartathlon in 1983 and returned in 1984 to run 20:25, a course record that stood until Fotis Zisimopoulos ran 19:55:09 in 2023.
Defining performances
Performance history
Selected results, not a complete race history. Rankings and record descriptions reflect the cited sources at their review dates. Distances may use different rounding conventions.
| Date | Event | Performance | Result | Source |
|---|---|---|---|---|
| Cliff Young Australian Six Day RaceSix-day track | 1,036.800 km | World best at the time | View ↗ | |
| Adelaide 24 Hour24-hour track | 303.506 km | World record at the time | View ↗ | |
| Surgeres 48 Hour48-hour track | 473.495 km | World record at the time | View ↗ | |
| Sri Chinmoy 1,000 Mile Race1,000-mile track | 10d 10:30:36 | Guinness world record | View ↗ | |
| Spartathlon246 km road | 20:25:00 | Winner | View ↗ |
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