Masamichi (千葉正道) Chiba
ID 177552
Born : 1961 Cat. M65 Ultrarunner since 2009 JPN
51
DUV-index ?Largest integer N such that the runner has at least N credited races of at least N km.
53
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
24,7%
Rank quotient ?This runner's calculation uses 57 eligible race(s): Σ(rank − 1) = 6 325; Σ finishers = 25 657. 6 325 / 25 657 × 100 = 24.65%. A win adds 0 to the numerator. Lower is better.

Totals

Ultras completed57
Km — ultra races5 001 km
> 100 km3
Longest race123,0 km
3rd Utsukushima Fukushima Journey Run 123K — 19/9/2020

Km per year (ultra races)

547
6 races
2022
544
6 races
2023
428
5 races
2024
530
6 races
2025
275
3 races
2026

Race types (share of distance)

Road97,8%
Trail2,2%

Wins & podiums (ultra)

🏆 Win0
🏆 Win M0
🏅 Top 31
🏅 Top 3 M1
Longest winning streak0
Current streak0

Records

50 km4h14'47100 km9h42'02

HISTORY

57 race(s)
DateRacePerf.Rk
2026
05.07 75km JPN4th Mt. Gassan Foot Ultra Marathon 9:37:04 h74
14.06 100km JPN20th Iwate Ginga 100km Marathon Challenge 11:42:17 h226
17.05 100km JPN32th Yatsugatake Nobeyama 100 km 13:19:28 h686
2025
28.09 100km JPN33. Akita Nairiku 100km Marathon 11:21:56 h120
06.07 75km JPN3rd Mt. Gassan Foot Ultra Marathon 8:41:42 h25
08.06 100km JPN19th Iwate Ginga 100km Marathon Challenge 10:41:10 h142
18.05 100km JPN31th Yatsugatake Nobeyama 100 km 12:45:20 h476
20.04 100km JPN6th Yamadera Zao 100 km Ultra Marathon 11:42:27 h15
30.03 55km JPN7th Ishinomaki Tozan Marathon 55km 7:43:22 h27
2024
22.09 100km JPN32. Akita Nairiku 100km Marathon 11:11:36 h73
31.08 53km JPN1st Sendai Ultra 50km Night Run 5:57:02 h2 🥈
07.07 75km JPN2nd Mt. Gassan Foot Ultra Marathon 8:42:27 h20
09.06 100km JPN12th Hida Takayama 100 km Ultramarathon 11:47:24 h455
21.04 100km JPN5th Yamadera Zao 100 km Ultra Marathon 11:18:34 h19
2023
24.09 100km JPN31. Akita Nairiku 100km Marathon 10:38:24 h84
09.07 75km JPN1st Mt. Gassan Foot Ultra Marathon 8:44:57 h25
01.07 8h JPN29th 8-Hour Endurance Race Tokorozawa 68.600 km24
11.06 100km JPN17th Iwate Ginga 100km Marathon Challenge 10:05:51 h65
04.06 100km JPN2. OSJ Aizu Bandaisan Ultramarathon - 100 km 11:58:50 h37
23.04 100km JPN4th Yamadera Zao 100 km Ultra Marathon 11:33:52 h11
2022
05.11 73km JPN1st Kosaka Pass Ultra Run 8:36:25 h4
25.09 100km JPN30. Akita Nairiku 100km Marathon 9:42:02 h39
03.07 8h JPN28th 8-Hour Endurance Race Tokorozawa 73.500 km35
12.06 100km JPN16th Iwate Ginga 100km Marathon Challenge 10:19:40 h115
05.06 100km JPN1. OSJ Aizu Bandaisan Ultramarathon - 100 km 11:13:03 h66
24.04 100km JPN3rd Yamadera Zao 100 km Ultra Marathon 15:40:53 h10
2021
14.11 47.2km JPN2nd Miyagi Yumeguri Ultra Run 4:56:00 h11
31.10 55km JPN2nd Yamadera Zao 100 km Ultra Marathon 5:56:56 h44
04.07 8h JPN27th 8-Hour Endurance Race Tokorozawa 83.300 km33
2020
19.09 123km JPN3rd Utsukushima Fukushima Journey Run 123K 16:31:23 h33
2019
19.10 51.4km JPN10th Inagawa 100km Ultra-Marathon 6:19:24 h196
22.09 100km JPN29. Akita Nairiku 100km Marathon 9:57:10 h71
07.09 115km JPN3rd Miyagi Yumeguri Ultra Marathon - 115 km 14:10:32 h7
09.06 100km JPN15th Iwate Ginga 100km Marathon Challenge 9:54:02 h62
21.04 100km JPN1st Yamadera Zao 100 km Ultra Marathon 12:52:10 h28
2018
20.10 100km JPN9th Inagawa 100km Ultra-Marathon 11:08:07 h12
23.09 100km JPN28. Akita Nairiku 100km Marathon 11:54:23 h196
2017
21.10 100km JPN8th Inagawa 100km Ultra-Marathon 11:05:46 h8
24.09 100km JPN27. Akita Nairiku 100km Marathon 9:54:17 h47
02.09 115km JPN1st Miyagi Yumeguri Ultra Marathon - 115 km 11:54:03 h10
11.06 100km JPN13th Iwate Ginga 100km Marathon Challenge 9:59:19 h130
04.06 78km JPN24. Ultramarathon Okumusashi 8:24:38 h289
2016
15.10 100km JPN7th Inagawa 100km Ultra-Marathon 11:17:50 h8
25.09 100km JPN26. Akita Nairiku 100km Marathon 10:05:12 h58
12.06 100km JPN12th Iwate Ginga 100km Marathon Challenge 10:30:09 h121
05.06 60km JPN4th Tokyo Shibamata 60 km 5:34:56 h53
2015
27.09 100km JPN25. Akita Nairiku 100km Marathon 9:54:59 h78
14.06 50km JPN11th Iwate Ginga 50km Marathon Challenge 4:14:47 h21
2014
28.09 100km JPN24. Akita Nairiku 100km Marathon 10:29:42 h117
08.06 50km JPN10th Iwate Ginga 50km Marathon Challenge 4:25:13 h25
2013
22.09 100km JPN23. Akita Nairiku 100km Marathon 11:43:42 h258
09.06 50km JPN9th Iwate Ginga 50km Marathon Challenge 4:52:47 h55
2012
23.09 100km JPN22. Akita Nairiku 100km Marathon 12:00:28 h348
10.06 50km JPN8th Iwate Ginga 50km Marathon Challenge 5:18:40 h104
2011
25.09 100km JPN21. Akita Nairiku 100km Marathon 12:39:11 h458
2010
26.09 100km JPN20. Akita Nairiku 100km Marathon 12:45:30 h575
2009
27.09 50km JPN19. Akita Nairiku 50km Marathon 5:07:28 h51