Kouichi (正木幸一) Masaki
Born : 1955 Cat. M70 Ultrarunner since 2012 JPN
47
DUV-index ?Largest integer N such that the runner has at least N credited races of at least N km.
52
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
1
Countries visited ?JPNJapan
78,7%
Rank quotient ?This runner's calculation uses 48 eligible race(s): Σ(rank − 1) = 15 058; Σ finishers = 19 141. 15 058 / 19 141 × 100 = 78.67%. A win adds 0 to the numerator. Lower is better.

Totals

Ultras completed48
Km — ultra races4 207 km
> 100 km16
Longest race142,0 km

Km per year (ultra races)

65
1 race
2022
407
4 races
2023
643
6 races
2024
404
4 races
2025
634
6 races
2026

Race types (share of distance)

Road54,5%
Trail22,5%
Ult.Walk23,1%

HISTORY

48 race(s)
DateRacePerf.Rk
2026
06.06 125km JPN10th Fujisan Issyu Walking 26:15:14 h197
16.05 102km JPN5th Kobe Akashi Ultra Marathon 22:23:32 h105
02.05 100km JPN9th Ultra Walking around Lake Biwa 21:25:15 h70
07.03 100km JPN6th Nihondaira and Suruganokuni Ultra Run 24:12:07 h90
21.02 105km JPN1st Lake Hamana and the Enshu Tokaido Ultra 25:16:51 h167
10.01 102km JPN3rd Nara Mahoroba Ultra Walking 24:55:31 h235
2025
17.05 102km JPN4th Kobe Akashi Ultra Marathon 23:59:10 h120
04.05 100km JPN8th Ultra Walking around Lake Biwa 22:53:37 h102
01.02 100km JPN5th Nihondaira and Suruganokuni Ultra Run 26:38:07 h108
11.01 102km JPN2nd Nara Mahoroba Ultra Walking 26:32:09 h196
2024
23.11 103km JPN3rd Kyoto Ultra Walking 110km 26:31:37 h209
14.09 100km JPN10th Nishi Seto Expressway Ultra Run 27:34:00 h233
08.06 110km JPN2nd Awaji Island Round Ultra 25:12:56 h87
25.05 125km JPN8th Fujisan Issyu Walking 29:02:12 h182
04.05 102km JPN3rd Kobe Akashi Ultra Marathon 25:43:40 h162
06.04 103km JPN7th Ultra Walking around Lake Biwa 23:29:34 h147
2023
25.11 110km JPN2nd Kyoto Ultra Walking 110km 27:08:51 h125
28.10 104km JPN4th Shodoshima Round Ultra Run 24:06:50 h113
16.09 100km JPN9th Nishi Seto Expressway Ultra Run 27:18:43 h214
25.02 93km JPN3rd Nihondaira and Suruganokuni Ultra Run 23:33:22 h45
2022
17.07 65km JPN2nd Yamaguchi Hagi Return 13:47:42 h275
2021
15.05 125km JPN1st Sengoku Crossroads Ultra Run 24:15:55 h41
2020
31.10 104km JPN1st Shodoshima Round Ultra Run 22:32:00 h90
20.09 80km JPN6th Nishi Seto Expressway Ultra Run 16:59:59 h109
2019
12.05 50km JPN23th 50 km Ultramarathon Ako Seaside Park 6:20:33 h44
2018
30.09 64km JPN5th Naeba-Sanroku Geopark Tsunan Ultramarathon 64K 9:32:18 h39
03.06 78km JPN25. Ultramarathon Okumusashi 11:03:10 h1087
14.04 70km JPN13th Toda Saiko 70 km 8:26:38 h458
2017
23.09 75km JPN4th SkyView Ultra-Trail 60 - Yamada Noboru Memorial Cup 23:34:33 h240
03.09 49.6km JPN6th Trainic world Ogose-Tokigawa Trail Run 50km 10:11:55 h280
04.06 78km JPN24. Ultramarathon Okumusashi 10:27:22 h1013
2016
11.12 71.7km JPN3rd Izu Trail Journey 14:06:09 h1294
19.11 52km JPN2nd FunTrails50K Two Lakes&Green line 10:43:16 h333
26.06 72.7km JPN3. Spatrail - Shima to Kusatsu 13:00:05 h710
24.04 100km JPN26th Fuji 5 Lakes 100 km Challenge 13:21:26 h920
2015
27.10 45km JPN7th Shinshu-Togakushi Trail Run Race 9:17:22 h268
17.10 100km JPN6th Inagawa 100km Ultra-Marathon 14:51:48 h154
06.09 49.6km JPN4th Trainic world Ogose-Tokigawa Trail Run 50km 9:42:06 h269
22.06 77km JPN22. Ultramarathon Okumusashi 10:37:54 h1082
11.04 70km JPN10th Toda Saiko 70 km 8:56:49 h442
2014
31.08 48km JPN1st Tsukuba Renjyo 48 km Road & Trail Run 7:16:18 h99
27.07 77km JPN21. Ultramarathon Okumusashi 11:46:26 h986
20.07 65km JPN5th Nozawa Onsen 4100D Mountain Trail 14:47:44 h376
12.04 70km JPN9th Toda Saiko 70 km 8:37:24 h360
2013
15.09 142km JPN16th Karisakatoge beyond Chichibu Run 24:45:06 h150
28.07 77km JPN20. Ultramarathon Okumusashi 10:51:55 h1036
15.06 12h JPN12. Tokyo Challenge 12 hours 78.400 km25
2012
01.09 12h JPN15. Hiratsuka 12 hour race 84.770 km19