Self-Transcendence Ten-Day winner
Covered 1,363.763 km to win the ten-day race in Moscow.
Source-checked athlete record · Updated Oct 12, 2026
Ivan Zaborsky
1,047.554 km six-day performer and 2026 Moscow ten-day champion
Ivan Zaborsky covered 1,047.554 km in six days in 2025 and won Moscow’s 2026 ten-day race with 1,363.763 km.
RussiaMoscowM35–39
The record so far
Ivan Zaborsky is a Russian fixed-time, multiday, and backyard ultrarunner from Moscow. At the 2025 GOMU Six-Day World Championship in France, he covered 1,047.554 km, finishing first and exceeding Matthieu Bonne’s ratified IAU world best by 2.035 km.
The 2025 performance has been described as a world record by GOMU and iRunFar. As of this profile’s October 2026 verification, however, the IAU record list still names Bonne’s 1,045.519 km as the current ratified world-best performance and does not list Zaborsky’s mark as pending. The two statuses are therefore presented separately.
Zaborsky extended his multiday record in 2026. He won the BUFF 72-Hour World Cup with 559.578 km and the Self-Transcendence Ten-Day Race in Moscow with 1,363.763 km. He also reached 121 yards (811.426 km) at Biotropika in June 2026, although the backyard format’s founder said that event’s results would not be recognized. Zaborsky is listed first on the neutral-athlete (AIN) roster for the 2026 Backyard World Team Championship, which starts on October 17.
Defining performances
Performance history
| Date | Event | Performance | Result | Source |
|---|---|---|---|---|
| Self-Transcendence Ten-Day Race MoscowTen-day road | 1,363.763 km | Winner | View ↗ | |
| Biotropika Ultra TrailBackyard ultraThe backyard format’s founder, Lazarus Lake, said the event’s results would not count because non-competitors were on the course. | 121 yards · 811.426 km | 3rd overall · Results not recognized | View ↗ | |
| BUFF 72-Hour World Cup72-hour road | 559.578 km | Winner | View ↗ | |
| Brazil 135 Ultra Journey240 km journey race | 29:37:57 | Winner | View ↗ | |
| Biotropika Ultra TrailBackyard ultra | 106 yards · 710.836 km | Winner | View ↗ | |
| GOMU Six-Day World ChampionshipSix-day road | 1,047.554 km | Winner · Organizer-recognized world record | View ↗ | |
| Authentic Phidippides Run490 km road | 52:52:28 | Winner · Course record | View ↗ |
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