Kazuki (山﨑一樹) Yamazaki

Born : 1967 Cat. M55 Ultrarunner since 2010

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 ?

Greece

Japan

36,3%

Rank quotient ?This runner's calculation uses 70 eligible race(s): Σ(rank − 1) = 6 984; Σ finishers = 19 255. 6 984 / 19 255 × 100 = 36.27%. A win adds 0 to the numerator. Lower is better.

Totals

Ultras completed74

Km — ultra races12 447 km

> 100 km53

> 160 km20

> 200 km20

Longest race516,0 km

21st River Road Foot Race 516 km — 30/4/2026

Km per year (ultra races)

1 666

2022

1 440

2023

1 482

2024

1 368

2025

721

2026

Race types (share of distance)

Road94,3%

Trail1,6%

Stage4,1%

Wins & podiums (ultra)

🏆 Win0

🏆 Win M0

🏅 Top 30

🏅 Top 3 M1

Longest winning streak0

Current streak0

Records

100 km10h47'38 50 mi10h26'17 100 mi26h16'39

HISTORY

72 race(s) · 4 stage(s) nested

Date		Race	Perf.	Rk
2026
30.04	516km	21st River Road Foot Race 516 km	4d 21:21:25 h	24
20.03	205km	2nd Izuichi Great Race 205km	35:04:38 h	4
2025
15.11	142km	7th Autumn leaves in Okumusashi / Chichibu Journey run	21:01:37 h	34
01–02.11	130km/2stages	3rd Mito Kaido Journey run	21:12:47 h	60
01.11	62.2km	3rd Mito Kaido Journey run - Stage 1	12:15:02 h	103
02.11	68.1km	3rd Mito Kaido Journey run - Stage 2	8:57:45 h	20
19.10	70km	32. Ultramarathon Okumusashi	9:03:44 h	273
13.09	250km	8th Utsukushima Fukushima Journey Run 250K	47:31:06 h	31
22.08	101km	12th World Cultural Heritage "Fuji" Foot Race	14:31:01 h	92
07.06	159km	6th Nikko Sennin Concentric Highway Journey Run	29:49:00 h	53
30.04	516km	20th River Road Foot Race 514 km	5d 07:48:55 h	55
2024
16.11	130km	2nd Mito Kaido Journey run	23:49:09 h	86
02.11	142km	6th Autumn leaves in Okumusashi / Chichibu Journey run	23:43:24 h	82
20.10	70km	31. Ultramarathon Okumusashi	7:56:05 h	160
23.08	101km	11th World Cultural Heritage "Fuji" Foot Race	14:09:43 h	72
08.06	159km	5th Nikko Sennin Concentric Highway Journey Run	28:05:59 h	52
30.04	514km	19th River Road Foot Race 514 km	4d 13:24:20 h	16
16–17.03	136km/2stages	12th Arakawa Riverside Journey Stage Race	19:37:53 h	44
16.03	82km	12th Arakawa Riverside Journey Stage Race - Stage 1	11:37:08 h	79
17.03	54.2km	12th Arakawa Riverside Journey Stage Race - Stage 2	8:00:45 h	70
09.03	230km	14th Little Edo Oedo 230k	34:44:00 h	25
2023
18.11	130km	1st Mito Kaido Journey run	24:54:54 h	127
28.10	147km	5th Autumn leaves in Okumusashi / Chichibu Journey run	24:35:37 h	108
18.08	101km	10th World Cultural Heritage "Fuji" Foot Race	15:20:32 h	88
17.06	159km	4th Nikko Sennin Concentric Highway Journey Run	26:16:39 h	12
04.06	78km	30. Ultramarathon Okumusashi	9:27:45 h	302
30.04	513km	18th River Road Foot Race 513 km	4d 06:13:34 h	8
18.03	82km	11th Arakawa Riverside Journey Stage Race - Stage 1	11:38:43 h	59
11.03	230km	13th Little Edo Oedo 230k	33:10:05 h	17
2022
29.10	146km	4th Autumn leaves in Okumusashi / Chichibu Journey run	21:43:39 h	48
15.10	150km	1st Yagurazawa Round Trip Pre-Tournament	28:22:40 h	44
30.09	246km	39. Spartathlon	34:41:19 h	109
20.08	101km	9th World Cultural Heritage "Fuji" Foot Race	14:19:05 h	46
05.06	78km	29. Ultramarathon Okumusashi	9:01:19 h	329
30.04	513km	17th River Road Foot Race 513 km	3d 21:37:27 h	9
02.04	120km	1st Saitama Romantic Road Chronicle Gaiden Shinryuu	18:33:49 h	9
21.03	81.6km	10th Arakawa Riverside Journey - 81.6 km	11:24:00 h	27
12.03	230km	12th Little Edo Oedo 230k	31:55:40 h	12
2021
30.10	146km	3rd Autumn leaves in Okumusashi / Chichibu Journey run	18:50:22 h	36
30.04	503km	16th River Road Foot Race 503 km	4d 00:25:36 h	7
03.04	80km	9th Arakawa Riverside Journey - 80 km	11:57:00 h	25
27.02	235km	11th Little Edo Oedo 235k	34:18:15 h	26
2020
24.10	146km	2nd Autumn leaves in Okumusashi / Chichibu Journey run	22:33:19 h	102
22.08	101km	8th World Cultural Heritage "Fuji" Foot Race	13:41:04 h	25
21.03	80km	8th Arakawa Riverside Journey - 80 km	10:26:17 h	12
22.02	235km	10th Little Edo Oedo 235k	32:13:38 h	25
2019
17.08	101km	7th World Cultural Heritage "Fuji" Foot Race	14:40:35 h	68
02.06	78km	26. Ultramarathon Okumusashi	9:15:45 h	593
30.04	514km	15th River Road Foot Race 514 km	5d 03:01:52 h	52
13.04	70km	14th Toda Saiko 70 km	7:13:38 h	170
16.03	80km	7th Arakawa Riverside Journey Stage Race - Stage 1	9:33:55 h	40
23.02	233km	9th Little Edo Oedo 230k	31:49:06 h	16
2018
16.09	100km	18th Tango 100 km Ultramarathon	13:28:11 h	729
19.08	101km	6th World Cultural Heritage "Fuji" Foot Race	13:00:00 h	30
03.06	78km	25. Ultramarathon Okumusashi	9:57:23 h	689
30.04	514km	14th River Road Foot Race 514 km	4d 06:20:13 h	8
14.04	70km	13th Toda Saiko 70 km	7:02:05 h	137
03.03	204km	8th Little Edo Oedo 200k	27:27:51 h	25
2017
20.08	97km	5th World Cultural Heritage "Fuji" Foot Race	11:44:00 h	15
04.06	78km	24. Ultramarathon Okumusashi	9:14:49 h	549
08.04	70km	12th Toda Saiko 70 km	6:40:47 h	104
04.03	204km	7th Little Edo Oedo 200k	26:40:40 h	30
2016
18.09	144km	19th Karisakatoge beyond Chichibu Run	22:58:19 h	63
24.04	118km	26th Fuji 5 Lakes 118 km Challenge	13:01:38 h	175
05.03	204km	6th Little Edo Oedo 200k	32:29:26 h	96
2015
23.08	97km	3rd World Cultural Heritage "Fuji" Foot Race	12:25:00 h	16
19.04	118km	25th Fuji 5 Lakes 118 km Challenge	13:33:57 h	194
28.02	112km	5th Oedo Night run 112k	13:57:16 h	12
2014
30.08	103km	2nd World Cultural Heritage "Fuji" Foot Race	12:45:00 h	15
20.04	108km	24th Fuji 5 Lakes 108 km Challenge	11:32:27 h	96
2013
24.08	101km	1st World Cultural Heritage "Fuji" Foot Race	12:23:10 h	10
21.04	112km	23rd Fuji 5 Lakes 112 km Challenge	12:20:00 h	35
02.03	111km	3rd Oedo Night run 111k	15:03:25 h	11
2012
22.04	112km	22nd Fuji 5 Lakes 112 km Challenge	12:52:50 h	176
2011
30.04	112km	21st Fuji 5 Lakes 112 km Challenge	12:03:57 h	93
2010
25.04	100km	20th Fuji 5 Lakes 100 km Challenge	10:47:38 h	131

Filter

Runner	Races in common

DUV-index calculation details

#	Date	Race	Credited km	DUV-index+
✓ 1	30/4/2026	21st River Road Foot Race 516 km	516,00	×5
✓ 2	30/4/2025	20th River Road Foot Race 514 km	516,00	×5
✓ 3	30/4/2024	19th River Road Foot Race 514 km	514,00	×5
✓ 4	30/4/2019	15th River Road Foot Race 514 km	514,00	×5
✓ 5	30/4/2018	14th River Road Foot Race 514 km	514,00	×5
✓ 6	30/4/2023	18th River Road Foot Race 513 km	513,00	×5
✓ 7	30/4/2022	17th River Road Foot Race 513 km	513,00	×5
✓ 8	30/4/2021	16th River Road Foot Race 503 km	503,00	×5
✓ 9	13/9/2025	8th Utsukushima Fukushima Journey Run 250K	250,00	×2
✓ 10	30/9/2022	39. Spartathlon	246,00	×2
✓ 11	27/2/2021	11th Little Edo Oedo 235k	235,00	×2
✓ 12	22/2/2020	10th Little Edo Oedo 235k	235,00	×2
✓ 13	23/2/2019	9th Little Edo Oedo 230k	233,00	×2
✓ 14	9/3/2024	14th Little Edo Oedo 230k	230,00	×2
✓ 15	11/3/2023	13th Little Edo Oedo 230k	230,00	×2
✓ 16	12/3/2022	12th Little Edo Oedo 230k	230,00	×2
✓ 17	20/3/2026	2nd Izuichi Great Race 205km	205,00	×2
✓ 18	3/3/2018	8th Little Edo Oedo 200k	204,00	×2
✓ 19	4/3/2017	7th Little Edo Oedo 200k	204,00	×2
✓ 20	5/3/2016	6th Little Edo Oedo 200k	204,00	×2
✓ 21	7/6/2025	6th Nikko Sennin Concentric Highway Journey Run	159,00	×1
✓ 22	8/6/2024	5th Nikko Sennin Concentric Highway Journey Run	159,00	×1
✓ 23	17/6/2023	4th Nikko Sennin Concentric Highway Journey Run	159,00	×1
✓ 24	15/10/2022	1st Yagurazawa Round Trip Pre-Tournament	150,00	×1
✓ 25	28/10/2023	5th Autumn leaves in Okumusashi / Chichibu Journey run	147,00	×1
✓ 26	29/10/2022	4th Autumn leaves in Okumusashi / Chichibu Journey run	146,00	×1
✓ 27	30/10/2021	3rd Autumn leaves in Okumusashi / Chichibu Journey run	146,00	×1
✓ 28	24/10/2020	2nd Autumn leaves in Okumusashi / Chichibu Journey run	146,00	×1
✓ 29	18/9/2016	19th Karisakatoge beyond Chichibu Run	144,00	×1
✓ 30	15/11/2025	7th Autumn leaves in Okumusashi / Chichibu Journey run	142,00	×1
✓ 31	2/11/2024	6th Autumn leaves in Okumusashi / Chichibu Journey run	142,00	×1
✓ 32	16/3/2024	12th Arakawa Riverside Journey Stage Race	136,00	×1
✓ 33	1/11/2025	3rd Mito Kaido Journey run	130,00	×1
✓ 34	16/11/2024	2nd Mito Kaido Journey run	130,00	×1
✓ 35	18/11/2023	1st Mito Kaido Journey run	130,00	×1
✓ 36	2/4/2022	1st Saitama Romantic Road Chronicle Gaiden Shinryuu	120,00	×1
✓ 37	24/4/2016	26th Fuji 5 Lakes 118 km Challenge	118,00	×1
✓ 38	19/4/2015	25th Fuji 5 Lakes 118 km Challenge	118,00	×1
✓ 39	28/2/2015	5th Oedo Night run 112k	112,00	×1
✓ 40	21/4/2013	23rd Fuji 5 Lakes 112 km Challenge	112,00	×1
✓ 41	22/4/2012	22nd Fuji 5 Lakes 112 km Challenge	112,00	×1
✓ 42	30/4/2011	21st Fuji 5 Lakes 112 km Challenge	112,00	×1
✓ 43	2/3/2013	3rd Oedo Night run 111k	111,00	×1
✓ 44	20/4/2014	24th Fuji 5 Lakes 108 km Challenge	108,00	×1
✓ 45	30/8/2014	2nd World Cultural Heritage "Fuji" Foot Race	103,00	×1
✓ 46	22/8/2025	12th World Cultural Heritage "Fuji" Foot Race	101,00	×1
✓ 47	23/8/2024	11th World Cultural Heritage "Fuji" Foot Race	101,00	×1
✓ 48	18/8/2023	10th World Cultural Heritage "Fuji" Foot Race	101,00	×1
✓ 49	20/8/2022	9th World Cultural Heritage "Fuji" Foot Race	101,00	×1
✓ 50	22/8/2020	8th World Cultural Heritage "Fuji" Foot Race	101,00	×1
✓ 51	17/8/2019	7th World Cultural Heritage "Fuji" Foot Race	101,00	×1
✓ 52	19/8/2018	6th World Cultural Heritage "Fuji" Foot Race	101,00	×1
✓ 53	24/8/2013	1st World Cultural Heritage "Fuji" Foot Race	101,00	×1
✓ 54	16/9/2018	18th Tango 100 km Ultramarathon	100,00	×1
✓ 55	25/4/2010	20th Fuji 5 Lakes 100 km Challenge	100,00	×1
✓ 56	20/8/2017	5th World Cultural Heritage "Fuji" Foot Race	97,00	—
✓ 57	23/8/2015	3rd World Cultural Heritage "Fuji" Foot Race	97,00	—
✓ 58	21/3/2022	10th Arakawa Riverside Journey - 81.6 km	81,60	—
✓ 59	3/4/2021	9th Arakawa Riverside Journey - 80 km	80,00	—
✓ 60	21/3/2020	8th Arakawa Riverside Journey - 80 km	80,00	—
✓ 61	4/6/2023	30. Ultramarathon Okumusashi	78,00	—
✓ 62	5/6/2022	29. Ultramarathon Okumusashi	78,00	—
✓ 63	2/6/2019	26. Ultramarathon Okumusashi	78,00	—
✓ 64	3/6/2018	25. Ultramarathon Okumusashi	78,00	—
✓ 65	4/6/2017	24. Ultramarathon Okumusashi	78,00	—
✓ 66	19/10/2025	32. Ultramarathon Okumusashi	70,00	—
✓ 67	20/10/2024	31. Ultramarathon Okumusashi	70,00	—
✓ 68	13/4/2019	14th Toda Saiko 70 km	70,00	—
✓ 69	14/4/2018	13th Toda Saiko 70 km	70,00	—
✓ 70	8/4/2017	12th Toda Saiko 70 km	70,00	—