Koichi (岩立幸一) Iwatate
ID 463860
Born : 1971 Cat. M55 Ultrarunner since 2013 JPN
63
DUV-index ?Largest integer N such that the runner has at least N credited races of at least N km.
100
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
2
Countries visited ?JPNJapanTPETaiwan
25,8%
Rank quotient ?This runner's calculation uses 70 eligible race(s): Σ(rank − 1) = 5 084; Σ finishers = 19 713. 5 084 / 19 713 × 100 = 25.79%. A win adds 0 to the numerator. Lower is better.

Totals

Ultras completed70
Km — ultra races13 631 km
> 100 km43
> 160 km34
> 200 km30
> 24h20
> 48h7
Longest race1 521,0 km
Across Honshu Lengthwise Foot Race — 19/9/2020

Km per year (ultra races)

1 093
4 races
2022
1 694
6 races
2023
1 674
7 races
2024
956
5 races
2025
516
1 race
2026

Race types (share of distance)

Road83,5%
Trail11,7%
Elim.4,8%

Wins & podiums (ultra)

🏆 Win6
🏆 Win M6
🏅 Top 312
🏅 Top 3 M12
Longest winning streak1
Current streak0

Records

50 km6h43'54100 km8h45'36100 mi19h52'1924 h240,50 km48 h362,09 kmBackyard38 loops

HISTORY

70 race(s) · 5 split(s) nested
DateRacePerf.Rk
2026
30.04 516km JPN21st River Road Foot Race 516 km 4d 14:46:58 h17
2025
12.10 24h JPN3rd Aizu Yanaizu Akabeko Marathon - 24h 147.000 km12
13.09 24h JPN20. Shonan Int. Relay Marathon 24 Hour Run 105.127 km22
21.06 24h JPN20th Green Charity Marathon Tokyo - Hard Run 24H 123.500 km38
23.05 48h JPN4th Hirosaki 48h Ultra Run 261.965 km10
21.02 48h TPE14th Taipei 48hr Ultra Marathon 318.511 km15
2024
01.11 Backyard Ultra JPN5th Last Samurai Standing Backyard Ultra - Fukushima 234.710 km (35h)8
14.09 250km JPN7th Utsukushima Fukushima Journey Run 250K 40:23:44 h10
13.07 266km JPN8th Michinoku Tsugaru Journey Run 266K 43:26:02 h8
20.05 48h JPN3rd Hirosaki 48h Ultra Run 362.093 km1 🏆
03.05 251km JPN19th River Road Foot Race 251 km 35:55:19 h7
20.04 110km JPN30. Sakura Michi Kokusai Nature Run (Half) 12:39:00 h34
07.01 200km JPN4th Japan Trophy 200 28:16:01 h20
2023
23.11 Backyard Ultra JPN4th Last Samurai Standing Backyard Ultra - Fukushima 254.828 km (38h)4
15.07 266km JPN7th Michinoku Tsugaru Journey Run 263K 42:04:52 h3 🥉
26.05 48h JPN2nd Hirosaki 48h Ultra Run 225.000 km22
30.04 513km JPN18th River Road Foot Race 513 km 3d 17:44:41 h5
21.04 250km JPN29. Sakura Michi Kokusai Nature Run 27:36:00 h5
11.03 24h JPN15th Jingu Gaien 24 Hour Challenge 185.094 km38
2022
19.11 Backyard Ultra JPN3rd Last Samurai Standing Backyard Ultra - Fukushima 160.944 km (24h)12
16.07 24h JPN28th Fuji Hokuroku Park 24h 159.600 km6
21.05 48h JPN1st Hirosaki 48h Ultra Run 259.139 km9
30.04 513km JPN17th River Road Foot Race 513 km 3d 16:10:12 h6
2021
30.10 146km JPN3rd Autumn leaves in Okumusashi / Chichibu Journey run 19:54:10 h52
04.07 8h JPN27th 8-Hour Endurance Race Tokorozawa 58.800 km262
30.04 503km JPN16th River Road Foot Race 503 km 4d 02:37:02 h11
27.02 235km JPN11th Little Edo Oedo 235k 27:44:44 h3 🥉
2020
19.09 1521km JPNAcross Honshu Lengthwise Foot Race 14d 11:35:00 h1 🏆
05.07 8h JPN26th 8-Hour Endurance Race Tokorozawa 73.500 km45
22.02 235km JPN10th Little Edo Oedo 235k 27:18:12 h3 🥉
2019
14.09 24h JPN14. Shonan Int. Relay Marathon 24 Hour Run 240.500 km1 🏆
13.07 100mi JPN12th OSJ Ontake 100 Mile Ultra Trail 19:52:19 h10
01.06 24h JPN18. Green Charity Marathon Tokyo - Hard Run 24H 208.500 km3 🥉
20.04 250km JPN26. Sakura Michi Kokusai Nature Run 25:27:00 h2 🥈
24.03 100km JPN1st Ibaraki 100k Ultra Marathon 8:45:36 h22
23.02 233km JPN9th Little Edo Oedo 230k 27:12:19 h3 🥉
2018
10.11 24h JPN13th Jingu Gaien 24 Hour Challenge 156.251 km87
20.10 100km JPN1st Tokyo Katsushika Ultra Marathon - 100km 9:25:12 h4
07.10 71.5km JPN26th Hasetsune Cup - Japan Mountain Endurance Race 16:49:30 h558
29.09 24h JPN3rd Coedo Kawagoe Running Fest 24-hours run 202.400 km1 🏆
02.06 24h JPN17. Green Charity Marathon Tokyo - Hard Run 24H 117.500 km50
21.04 250km JPN25. Sakura Michi Kokusai Nature Run 35:26:00 h68
2017
11.11 24h JPN12th Jingu Gaien 24 Hour Challenge 214.716 km18
08.10 71.5km JPN25th Hasetsune Cup - Japan Mountain Endurance Race 10:58:28 h90
30.09 24h JPN2nd Coedo Kawagoe Running Fest 24-hours run 221.340 km1 🏆
15.07 100km JPN10th OSJ Ontake 100km Ultra Trail 13:41:07 h196
04.06 100km JPN5th Tokyo Shibamata 100 km 11:31:48 h501
20.05 106km JPN2nd Trainic World 100 km in Sai-No-Kuni 27:46:59 h122
23.04 100km JPN27th Fuji 5 Lakes 100 km Challenge 9:42:52 h106
04.03 233km JPN7th Little Edo Oedo 230k 26:57:19 h1 🏆
2016
13.11 50km JPN8th Kanna Mountain Run 6:43:54 h11
09.10 71.5km JPN24th Hasetsune Cup - Japan Mountain Endurance Race 16:40:44 h914
28.08 70km JPN3rd Tsukuba Renjyo 70 km Road & Trail Run 8:04:30 h24
10.07 49.6km JPN5th Trainic world Ogose-Tokigawa Trail Run 50km 8:13:13 h51
05.06 78km JPN23. Ultramarathon Okumusashi 6:55:32 h69
29.04 49km JPN9th Ishioka Trail Run 5:23:21 h26
05.03 233km JPN6th Little Edo Oedo 230k 32:19:35 h11
2015
30.08 70km JPN2nd Tsukuba Renjyo 70 km Road & Trail Run 9:37:45 h94
12.07 8h JPN21th 8-Hour Endurance Race Tokorozawa - 3 tai 49.395 km85
22.06 77km JPN22. Ultramarathon Okumusashi 8:29:36 h364
28.05 100km JPN4th Tokorozawa Road to Morning - 100km 11:23:34 h8
28.02 203km JPN5th Little Edo Oedo 200k 31:45:45 h86
2014
31.08 70km JPN1st Tsukuba Renjyo 70 km Road & Trail Run 10:32:11 h61
27.07 77km JPN21. Ultramarathon Okumusashi 9:40:50 h387
06.07 8h JPN20th 8-Hour Endurance Race Tokorozawa - 3 tai 71.412 km22
06.04 100km JPN65. Tsurunuma 100 km 9:25:39 h8
2013
10.11 50km JPN5th Kanna Mountain Run 8:12:07 h42
08.09 52km JPN64. Tsurunuma 52 km 4:45:53 h24
28.07 77km JPN20. Ultramarathon Okumusashi 8:33:59 h320
02.03 91km JPN3rd Little Edo 91km 11:30:48 h14