Ryuichi (堺隆一) Sakai

Born : 1960 Cat. M65 Ultrarunner since 2006

DUV-index ?Largest integer N such that the runner has at least N credited races of at least N km.

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

Countries visited ?

Japan

22,4%

Rank quotient ?This runner's calculation uses 68 eligible race(s): Σ(rank − 1) = 7 091; Σ finishers = 31 599. 7 091 / 31 599 × 100 = 22.44%. A win adds 0 to the numerator. Lower is better.

Totals

Ultras completed68

Km — ultra races7 434 km

> 100 km18

> 160 km12

> 200 km9

> 24h8

Longest race250,0 km

22. Sakura Michi Kokusai Nature Run — 18/4/2015

Km per year (ultra races)

224

2022

213

2023

2024

130

2025

2026

Race types (share of distance)

Road80,5%

Trail19,5%

Wins & podiums (ultra)

🏆 Win0

🏆 Win M0

🏅 Top 31

🏅 Top 3 M1

Longest winning streak0

Current streak0

Records

100 km9h14'59 6 h63,64 km 12 h115,15 km 24 h182,29 km

HISTORY

68 race(s) · 4 split(s) nested

Date		Race	Perf.	Rk
2025
13.09	12h	20. Shonan Int. Relay Marathon 12 Hour Run	60.319 km	19
20.04	70km	16th 70 km Ultra Maranic Osaka	9:17:27 h	120
2023
08.04	71km	18th Toda Saiko 70 km	7:19:13 h	72
11.03	24h	15th Jingu Gaien 24 Hour Challenge	141.543 km	69
11.03	6h	15th Jingu Gaien 24 Hour Challenge - 6h Split	52.960 km	69
11.03	12h	15th Jingu Gaien 24 Hour Challenge -12h Split	87.384 km	75
2022
29.10	170km	9th Setouchi Angya - 170 km	26:59:00 h	15
03.07	8h	28th 8-Hour Endurance Race Tokorozawa	53.900 km	162
2019
02.11	222km	6th Setouchi Angya 2019	40:36:00 h	26
30.06	100km	34. Lake Saroma 100 km Ultramarathon	11:14:23 h	869
13.04	70km	14th Toda Saiko 70 km	7:34:15 h	217
24.03	100km	1st Ibaraki 100k Ultra Marathon	12:47:43 h	343
20.01	100km	29th Miyako 100 km Ultramarathon	11:32:02 h	79
2018
15.09	12h	21. Hiratsuka 12 hour race	96.900 km	11
04.08	24h	18th 24-hour relay & solo marathon Kobe	122.400 km	55
30.06	8h	24th 8-Hour Endurance Race Tokorozawa	53.900 km	116
2016
27.03	70km	2nd Osaka Yodogawa 70 km Ultra Marathon	6:26:23 h	7
2015
01.08	24h	15th 24-hour relay & solo marathon Kobe	120.700 km	36
22.06	77km	22. Ultramarathon Okumusashi	8:10:31 h	286
14.06	100km	11th Iwate Ginga 100km Marathon Challenge	11:20:20 h	245
17.05	100km	21st Yatsugatake Nobeyama 100 km	10:53:54 h	185
18.04	250km	22. Sakura Michi Kokusai Nature Run	32:12:58 h	33
29.03	70km	1st Osaka Yodogawa 70 km Ultra Marathon	6:19:13 h	15
2014
08.11	24h	9th Jingu Gaien 24 Hour Challenge	108.614 km	100
08.11	6h	9th Jingu Gaien 24 Hour Challenge - 6h Split	60.930 km	43
08.11	12h	9th Jingu Gaien 24 Hour Challenge -12h Split	104.640 km	53
12.10	100km	10th Echigo Kubikino 100km Ultramarathon	10:29:25 h	182
13.09	12h	17. Hiratsuka 12 hour race	95.150 km	11
27.07	77km	21. Ultramarathon Okumusashi	9:36:39 h	363
06.07	8h	20th 8-Hour Endurance Race Tokorozawa - 3 tai	58.428 km	58
21.06	6h	13. Tokyo Challenge 6 hours	56.350 km	16
08.06	100km	10th Iwate Ginga 100km Marathon Challenge	11:20:27 h	270
2013
14.09	12h	16. Hiratsuka 12 hour race	51.900 km	26
03.08	24h	14th 24-hour relay & solo marathon Kobe	50.000 km	84
28.07	77km	20. Ultramarathon Okumusashi	8:41:25 h	341
07.07	8h	19th 8-Hour Endurance Race Tokorozawa - 3 tai	51.936 km	64
30.06	100km road race	28. Lake Saroma 100 km Ultramarathon	9:36:52 h	220
15.06	12h	12. Tokyo Challenge 12 hours	115.150 km	6
09.06	100km	9th Iwate Ginga 100km Marathon Challenge	10:37:54 h	164
19.05	100km	19th Yatsugatake Nobeyama 100 km	10:56:58 h	138
19.04	250km	20. Sakura Michi Kokusai Nature Run	31:44:00 h	17
2012
05.08	77km	19. Ultramarathon Okumusashi	8:34:46 h	220
08.07	8h	18th 8-Hour Endurance Race Tokorozawa - 3 tai	77.904 km	16
16.06	6h	11. Tokyo Challenge 6 hours	63.640 km	24
10.06	100km	8th Iwate Ginga 100km Marathon Challenge	11:16:11 h	212
21.04	250km	19. Sakura Michi Kokusai Nature Run	34:58:00 h	61
03.03	203km	2nd Little Edo Oedo 200k	28:42:20 h	20
2011
15.10	24h	6th Jingu Gaien 24 Hour Challenge	163.973 km	34
25.09	100km	21. Akita Nairiku 100km Marathon	9:14:59 h	29
07.08	77km	18. Ultramarathon Okumusashi	8:25:26 h	227
12.06	100km	7th Iwate Ginga 100km Marathon Challenge	11:20:07 h	161
21.05	12h	1st 12 hour Tokorozawa	91.895 km	25
16.04	250km	18. Sakura Michi Kokusai Nature Run	30:59:00 h	16
05.03	203km	1st Little Edo Oedo 200k	26:36:58 h	5
2010
09.10	100km	8th Echigo Kubikino 100km Ultramarathon	9:47:17 h	86
11.09	24h	5th Jingu Gaien 24 Hour Challenge	80.886 km	41
01.08	77km	17. Ultramarathon Okumusashi	7:44:19 h	98
04.07	8h	16th 8-Hour Endurance Race Tokorozawa - 3 tai	58.428 km	34
17.04	250km	17. Sakura Michi Kokusai Nature Run	34:08:00 h	45
2009
02.08	75km	16. Ultramarathon Okumusashi	7:30:20 h	129
02.05	250km	21. Yamaguchi 100 Hagi-O-Kan Maranic 250 km	38:09:07 h	22
11.04	70km	4th Toda Saiko 70 km	7:03:50 h	38
2008
11.10	100km	7th Echigo Kubikino 100km Ultramarathon	9:23:24 h	41
07.06	24h	6th Akiruno 24 Hour Race Japan Cup	182.294 km	3 🥉
03.05	140km	20. Yamaguchi 100 Hagi-O-Kan Maranic 140 km	20:17:58 h	32
12.04	70km	3rd Toda Saiko 70 km	6:20:15 h	20
2007
14.10	100km	13th River Shimanto 100km	11:06:38 h	255
05.08	75km	14. Ultramarathon Okumusashi	8:02:34 h	127
20.05	100km	3rd Iwate Ginga 100km Marathon Challenge	9:59:22 h	31
2006
09.10	100km	6th Echigo Kubikino 100km Ultramarathon	9:45:09 h	47
02.07	8h	12th 8-Hour Endurance Race Tokorozawa	75.900 km	12
08.04	60.7km	1st Toda Saiko 60 km	5:44:30 h	8

Filter

Runner	Races in common

DUV-index calculation details

#	Date	Race	Credited km	DUV-index+
✓ 1	18/4/2015	22. Sakura Michi Kokusai Nature Run	250,00	×3
✓ 2	19/4/2013	20. Sakura Michi Kokusai Nature Run	250,00	×3
✓ 3	21/4/2012	19. Sakura Michi Kokusai Nature Run	250,00	×3
✓ 4	16/4/2011	18. Sakura Michi Kokusai Nature Run	250,00	×3
✓ 5	17/4/2010	17. Sakura Michi Kokusai Nature Run	250,00	×3
✓ 6	2/5/2009	21. Yamaguchi 100 Hagi-O-Kan Maranic 250 km	250,00	×3
✓ 7	2/11/2019	6th Setouchi Angya 2019	222,00	×3
✓ 8	3/3/2012	2nd Little Edo Oedo 200k	203,00	×2
✓ 9	5/3/2011	1st Little Edo Oedo 200k	203,00	×2
✓ 10	7/6/2008	6th Akiruno 24 Hour Race Japan Cup	182,29	×2
✓ 11	29/10/2022	9th Setouchi Angya - 170 km	170,00	×2
✓ 12	15/10/2011	6th Jingu Gaien 24 Hour Challenge	163,97	×2
✓ 13	11/3/2023	15th Jingu Gaien 24 Hour Challenge	141,54	×2
✓ 14	3/5/2008	20. Yamaguchi 100 Hagi-O-Kan Maranic 140 km	140,00	×2
✓ 15	4/8/2018	18th 24-hour relay & solo marathon Kobe	122,40	×1
✓ 16	1/8/2015	15th 24-hour relay & solo marathon Kobe	120,70	×1
✓ 17	15/6/2013	12. Tokyo Challenge 12 hours	115,15	×1
✓ 18	8/11/2014	9th Jingu Gaien 24 Hour Challenge	108,61	×1
✓ 19	30/6/2019	34. Lake Saroma 100 km Ultramarathon	100,00	×1
✓ 20	24/3/2019	1st Ibaraki 100k Ultra Marathon	100,00	×1
✓ 21	20/1/2019	29th Miyako 100 km Ultramarathon	100,00	×1
✓ 22	14/6/2015	11th Iwate Ginga 100km Marathon Challenge	100,00	×1
✓ 23	17/5/2015	21st Yatsugatake Nobeyama 100 km	100,00	×1
✓ 24	12/10/2014	10th Echigo Kubikino 100km Ultramarathon	100,00	×1
✓ 25	8/6/2014	10th Iwate Ginga 100km Marathon Challenge	100,00	×1
✓ 26	30/6/2013	28. Lake Saroma 100 km Ultramarathon (JPN)	100,00	×1
✓ 27	9/6/2013	9th Iwate Ginga 100km Marathon Challenge	100,00	×1
✓ 28	19/5/2013	19th Yatsugatake Nobeyama 100 km	100,00	×1
✓ 29	10/6/2012	8th Iwate Ginga 100km Marathon Challenge	100,00	×1
✓ 30	25/9/2011	21. Akita Nairiku 100km Marathon	100,00	×1
✓ 31	12/6/2011	7th Iwate Ginga 100km Marathon Challenge	100,00	×1
✓ 32	9/10/2010	8th Echigo Kubikino 100km Ultramarathon	100,00	×1
✓ 33	11/10/2008	7th Echigo Kubikino 100km Ultramarathon	100,00	×1
✓ 34	14/10/2007	13th River Shimanto 100km	100,00	×1
✓ 35	20/5/2007	3rd Iwate Ginga 100km Marathon Challenge	100,00	×1
✓ 36	9/10/2006	6th Echigo Kubikino 100km Ultramarathon	100,00	×1
✓ 37	15/9/2018	21. Hiratsuka 12 hour race	96,90	×1
✓ 38	13/9/2014	17. Hiratsuka 12 hour race	95,15	×1
✓ 39	21/5/2011	1st 12 hour Tokorozawa	91,90	×1
✓ 40	11/9/2010	5th Jingu Gaien 24 Hour Challenge	80,89	×1
✓ 41	8/7/2012	18th 8-Hour Endurance Race Tokorozawa - 3 tai	77,90	×1
✓ 42	22/6/2015	22. Ultramarathon Okumusashi	77,00	×1
✓ 43	27/7/2014	21. Ultramarathon Okumusashi	77,00	×1
✓ 44	28/7/2013	20. Ultramarathon Okumusashi	77,00	×1
✓ 45	5/8/2012	19. Ultramarathon Okumusashi	77,00	×1
✓ 46	7/8/2011	18. Ultramarathon Okumusashi	77,00	×1
✓ 47	1/8/2010	17. Ultramarathon Okumusashi	77,00	×1
✓ 48	2/7/2006	12th 8-Hour Endurance Race Tokorozawa	75,90	×1
✓ 49	2/8/2009	16. Ultramarathon Okumusashi	75,00	×1
✓ 50	5/8/2007	14. Ultramarathon Okumusashi	75,00	×1
✓ 51	8/4/2023	18th Toda Saiko 70 km	71,00	×1
✓ 52	20/4/2025	16th 70 km Ultra Maranic Osaka	70,00	×1
✓ 53	13/4/2019	14th Toda Saiko 70 km	70,00	×1
✓ 54	27/3/2016	2nd Osaka Yodogawa 70 km Ultra Marathon	70,00	×1
✓ 55	29/3/2015	1st Osaka Yodogawa 70 km Ultra Marathon	70,00	×1
✓ 56	11/4/2009	4th Toda Saiko 70 km	70,00	×1
✓ 57	12/4/2008	3rd Toda Saiko 70 km	70,00	×1
✓ 58	16/6/2012	11. Tokyo Challenge 6 hours	63,64	—
✓ 59	8/4/2006	1st Toda Saiko 60 km	60,70	—
✓ 60	13/9/2025	20. Shonan Int. Relay Marathon 12 Hour Run	60,32	—
61	6/7/2014	20th 8-Hour Endurance Race Tokorozawa - 3 tai	58,43	—
62	4/7/2010	16th 8-Hour Endurance Race Tokorozawa - 3 tai	58,43	—
63	21/6/2014	13. Tokyo Challenge 6 hours	56,35	—
64	3/7/2022	28th 8-Hour Endurance Race Tokorozawa	53,90	—
65	30/6/2018	24th 8-Hour Endurance Race Tokorozawa	53,90	—
66	7/7/2013	19th 8-Hour Endurance Race Tokorozawa - 3 tai	51,94	—
67	14/9/2013	16. Hiratsuka 12 hour race	51,90	—
68	3/8/2013	14th 24-hour relay & solo marathon Kobe	50,00	—