Tomoko (關とも子) Seki
ID 810447
Born : 1968 Cat. W55 Ultrarunner since 2016 JPN
18
DUV-index ?Largest integer N such that the runner has at least N credited races of at least N km.
45
DUV-index+ ?Largest integer N such that the race distances provide at least N complete segments of N km in total. A single long race may therefore contribute several segments. See the DUV-Index tab for the detailed calculation. calculation details
4
Countries visited ?FRAFranceJPNJapanSUISwitzerlandUSAUnited States
43,0%
Rank quotient ?This runner's calculation uses 18 eligible race(s): Σ(rank − 1) = 2 102; Σ finishers = 4 889. 2 102 / 4 889 × 100 = 42.99%. A win adds 0 to the numerator. Lower is better.

Totals

Ultras completed19
Km — ultra races2 510 km
> 100 km17
> 160 km9
Longest race169,0 km
2nd Lake Biwa 100 — 7/10/2022

Km per year (ultra races)

169
1 race
2022
118
1 race
2023
109
1 race
2024
285
2 races
2025
212
2 races
2026

Race types (share of distance)

Road30,8%
Trail63,3%
Stage6,0%

Wins & podiums (ultra)

🏆 Win0
🏆 Win F0
🏅 Top 30
🏅 Top 3 F2
Longest winning streak0
Current streak0

Records

100 mi32h15'00

HISTORY

18 race(s) · 2 stage(s) nested
DateRacePerf.Rk
2026
28.02–01.03 150km/2stages JPN3rd Modern Japanese Silk Road Journey Run 20:37:25 h25
01.02 62km JPN4. Minuma Challenge 60 7:31:05 h50
2025
27.06 165km JPN4th Deep Japan Ultra 100 - 165 km 45:33:52 h57
20.04 120km JPN35th Fuji 5 Lakes Sparta Challenge 14:50:06 h392
2024
23.03 109km JPN2nd Hiroshima Wangan Trail Run 23:50:09 h154
2023
16.04 118km JPN33th Fuji 5 Lakes 118 km Challenge 14:12:09 h224
2022
07.10 169km JPN2nd Lake Biwa 100 2d 01:31:40 h138
2021
01.10 167km JPN1st Lake Biwa 100 2d 01:04:49 h55
2020
14.11 100Miles JPN2nd Sengenyama 100 32:15:00 h17
2019
21.04 118km JPN29th Fuji 5 Lakes 118 km Challenge 13:46:44 h189
2018
04.08 100mi USA31st Angeles Crest 100 Mile 32:34:48 h88
22.04 118km JPN28th Fuji 5 Lakes 118 km Challenge 13:15:52 h118
2017
07.10 100mi JPN4th OSJ Koumi 100 34:33:11 h100
28.07 165km SUILa MXtrem160 2d 07:05:34 h91
23.04 118km JPN27th Fuji 5 Lakes 118 km Challenge 12:53:29 h119
2016
08.10 100mi JPN3rd OSJ Koumi 100 33:41:52 h42
19.08 169km FRAUltra Tour des 4 Massifs (UT4M) Xtrem 2d 03:03:28 h183
24.04 118km JPN26th Fuji 5 Lakes 118 km Challenge 11:53:05 h78