David Zylstra
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Born : 1986
Cat. M40 Ultrarunner since 2017
10
DUV-index ?Largest integer N such that the runner has at least N credited races of at least N km.
25
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 ?
CanadaUnited States
CanadaUnited States71,0%
Rank quotient ?This runner's calculation uses 10 eligible race(s): Σ(rank − 1) = 788; Σ finishers = 1 110. 788 / 1 110 × 100 = 70.99%. A win adds 0 to the numerator. Lower is better.
Totals
Ultras completed10
Km — ultra races764 km
> 100 km2
Longest race119,1 km
11th Georgia Death Race — 25/3/2023
Km per year (ultra races)
2022
2023
2024
2025
2026
Race types (share of distance)
Trail100,0%
Records
HISTORY
10 race(s)| Date | Race | Perf. | Rk | |
|---|---|---|---|---|
| 2023 | ||||
| 25.03 | 74mi | 11th Georgia Death Race |
23:33:12 h | 133 |
| 2022 | ||||
| 24.09 | 50mi | 3rd Midwest Everest 50 Mile Race |
16:53:47 h | 5 |
| 20.08 | 50mi | 10th Squamish 50mi |
16:12:30 h | 325 |
| 2021 | ||||
| 18.09 | 50km | 8th The Barkley Fall Classic |
13:17:03 h | 175 |
| 2020 | ||||
| 07.11 | 74mi | 8th Georgia Death Race |
18:57:50 h | 18 |
| 26.09 | 50mi | 8th Hungerford Trail Race 50 Mile |
9:52:50 h | 21 |
| 2019 | ||||
| 19.01 | 50km | 8th Bear Bait 50K Ultramarathon |
6:07:19 h | 7 |
| 2018 | ||||
| 15.09 | 50km | 5th The Barkley Fall Classic |
11:33:26 h | 94 |
| 02.06 | 52.4mi | 8th Yankee Springs 52 Mile Trail Run |
11:37:04 h | 10 |
| 2017 | ||||
| 07.10 | 50km | 2nd Yankee Springs Fall Trail Run Festival |
5:55:26 h | 10 |
| Runner | Races in common |
|---|---|
DUV-index calculation details
| # | Date | Race | Credited km | DUV-index+ |
|---|---|---|---|---|
| ✓ 1 | 25/3/2023 | 11th Georgia Death Race | 119,09 | ×4 |
| ✓ 2 | 7/11/2020 | 8th Georgia Death Race | 119,09 | ×4 |
| ✓ 3 | 2/6/2018 | 8th Yankee Springs 52 Mile Trail Run | 84,33 | ×3 |
| ✓ 4 | 24/9/2022 | 3rd Midwest Everest 50 Mile Race | 80,47 | ×3 |
| ✓ 5 | 20/8/2022 | 10th Squamish 50mi | 80,47 | ×3 |
| ✓ 6 | 26/9/2020 | 8th Hungerford Trail Race 50 Mile | 80,47 | ×3 |
| ✓ 7 | 18/9/2021 | 8th The Barkley Fall Classic | 50,00 | ×2 |
| ✓ 8 | 19/1/2019 | 8th Bear Bait 50K Ultramarathon | 50,00 | ×2 |
| ✓ 9 | 15/9/2018 | 5th The Barkley Fall Classic | 50,00 | ×2 |
| ✓ 10 | 7/10/2017 | 2nd Yankee Springs Fall Trail Run Festival | 50,00 | ×2 |