Tsuyoshi (石塚剛史) Ishizuka
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Born : 1983
Cat. M40 Ultrarunner since 2015
12
DUV-index ?Largest integer N such that the runner has at least N credited races of at least N km.
28
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 ?Japan
Japan10,9%
Rank quotient ?This runner's calculation uses 12 eligible race(s): Σ(rank − 1) = 936; Σ finishers = 8 591. 936 / 8 591 × 100 = 10.90%. A win adds 0 to the numerator. Lower is better.
Totals
Ultras completed12
Km — ultra races989 km
> 100 km4
Longest race110,0 km
11th Shinetsu Five Mountains Trail 110km — 15/9/2019
Km per year (ultra races)
2022
2023
2024
2025
2026
Race types (share of distance)
Trail100,0%
Wins & podiums (ultra)
🏆 Win0
🏆 Win M0
🏅 Top 30
🏅 Top 3 M1
Longest winning streak0
Current streak0
Records
HISTORY
12 race(s)| Date | Race | Perf. | Rk | |
|---|---|---|---|---|
| 2025 | ||||
| 21.06 | 105km | 1st Kaga Spa by UTMB - Kaga Spa Trail Endurance100 |
23:10:17 h | 191 |
| 2024 | ||||
| 13.10 | 71.5km | 32th Hasetsune Cup - Japan Mountain Endurance Race |
11:49:33 h | 180 |
| 2023 | ||||
| 22.04 | 69km | 2nd KAI 69k |
9:42:40 h | 37 |
| 2021 | ||||
| 20.11 | 106km | 7th FunTrails100K Round |
19:05:06 h | 57 |
| 13.03 | 103.5km | 3rd Sengenyama 100 |
17:38:00 h | 4 |
| 2020 | ||||
| 13.12 | 66km | 7th Izu Trail Journey |
8:59:06 h | 196 |
| 2019 | ||||
| 15.09 | 110km | 11th Shinetsu Five Mountains Trail 110km |
18:08:50 h | 82 |
| 2018 | ||||
| 23.06 | 80km | 4th OSJ Yamanaka Onsen Trail Run |
15:00:41 h | 84 |
| 2016 | ||||
| 16.07 | 65km | 7th Nozawa Onsen 4100D Mountain Trail |
8:19:50 h | 15 |
| 2015 | ||||
| 31.10 | 71.5km | 23rd Hasetsune Cup - Japan Mountain Endurance Race |
9:32:55 h | 62 |
| 26.09 | 76.7km | 4th Shizuoka to Yamanashi |
10:46:46 h | 25 |
| 19.07 | 65km | 6th Nozawa Onsen 4100D Mountain Trail |
8:27:06 h | 15 |
| Runner | Races in common |
|---|---|
DUV-index calculation details
| # | Date | Race | Credited km | DUV-index+ |
|---|---|---|---|---|
| ✓ 1 | 15/9/2019 | 11th Shinetsu Five Mountains Trail 110km | 110,00 | ×3 |
| ✓ 2 | 20/11/2021 | 7th FunTrails100K Round | 106,00 | ×3 |
| ✓ 3 | 21/6/2025 | 1st Kaga Spa by UTMB - Kaga Spa Trail Endurance100 | 105,00 | ×3 |
| ✓ 4 | 13/3/2021 | 3rd Sengenyama 100 | 103,50 | ×3 |
| ✓ 5 | 23/6/2018 | 4th OSJ Yamanaka Onsen Trail Run | 80,00 | ×2 |
| ✓ 6 | 26/9/2015 | 4th Shizuoka to Yamanashi (STY) | 76,70 | ×2 |
| ✓ 7 | 13/10/2024 | 32th Hasetsune Cup - Japan Mountain Endurance Race | 71,50 | ×2 |
| ✓ 8 | 31/10/2015 | 23rd Hasetsune Cup - Japan Mountain Endurance Race | 71,50 | ×2 |
| ✓ 9 | 22/4/2023 | 2nd KAI 69k | 69,00 | ×2 |
| ✓ 10 | 13/12/2020 | 7th Izu Trail Journey | 66,00 | ×2 |
| ✓ 11 | 16/7/2016 | 7th Nozawa Onsen 4100D Mountain Trail | 65,00 | ×2 |
| ✓ 12 | 19/7/2015 | 6th Nozawa Onsen 4100D Mountain Trail | 65,00 | ×2 |