Anton Krupicka - Trail Runner Profile

Anton Krupicka is an American ultrarunner who won the Leadville Trail 100 in 2006 at 23, on his first ultramarathon, and again in 2007, becoming one of the defining figures of the sport's modern era. Known for running long, high-mileage weeks in minimalist shoes and for a distinctive shirtless, long

Anton Krupicka quick facts

Age: 43 (born 2 August 1983)
Nationality: United States
From: Near Niobrara, Nebraska
UTMB Index: no UTMB Index shown on the official profile (as of 6 October 2026, UTMB profile)
ITRA score: 705 (as of 27 August 2026, ITRA profile)
Key results: Leadville Trail 100: Winner 2006 and 2007; FKTs set: 28 fastest known times; Comeback: 3rd at Leadville in 2021, 15 years after his first win

UTMB Index and ITRA scores change after every race. The dates are when each number was read from the official profile.

Country: United States · Specialities: 100 miles, 50–100km

Right now: Returned to the Leadville 100 start line in August 2026 after years of injury interruptions.

Key facts

Leadville Trail 100: Winner 2006 and 2007
FKTs set: 28 fastest known times
Comeback: 3rd at Leadville in 2021, 15 years after his first win

An unknown who dominated Leadville

Krupicka entered the 2006 Leadville Trail 100 as a virtual unknown for his first ultramarathon and won by an hour and 45 minutes in 17:01:56. He successfully defended the title in 2007, and those two wins, at high altitude on a race with a long and storied history, established him as one of the sport's brightest talents almost overnight.

A distinctive approach to training and racing

Through his early and mid-twenties, Krupicka trained on 150 to 200 mile weeks in minimalist shoes, an approach that was unusual even by ultrarunning standards and that made him one of the sport's most closely watched athletes. Beyond his ultra wins, he has set 28 fastest known times on mountain routes across Colorado and beyond.

Injury, comeback, and a return to Leadville

Krupicka stopped racing ultras after 2015 as stress fractures and Achilles problems piled up. He made a partial comeback at the 2021 Leadville Trail 100, finishing third in 17:07:55, only six minutes slower than his 2006 winning time fifteen years earlier. After more injury setbacks, he returned to the Leadville start line again in August 2026.

How Anton runs

Krupicka is an old-school mountain runner whose career was built on volume and simplicity rather than structured intervals. Through his twenties he trained on very high mileage, often 150 to 200 miles a week, much of it on steep mountain terrain, in minimalist shoes and with a minimal approach to gear.

His racing reflected that training. He was strongest on long, sustained climbs at altitude, where years of aerobic volume let him hold an effort that others could not, and he was at his best on courses that rewarded relentless steady running rather than tactics or speed changes.

He is also a climber and scrambler. When a leg injury kept him off the trails in 2011 he took to the rock of Boulder's Flatirons and Eldorado Canyon, and he went on to set speed records on link-ups that combine running and easy free-solo scrambling, including a Double Quinfecta of the Flatirons in 4:07:17 in 2012. Much of his reputation comes from that time in the mountains away from racing. The volume, the minimalism and the time on steep ground were all part of the same approach to running in the mountains.

Where Anton is strongest

High-altitude 100-milers with long, sustained climbs, in the mould of Leadville, which he won on his first ultramarathon in 2006 and again in 2007, and mountain ultras up to about 100 miles, including Lavaredo in 2014.

His high-volume approach also came with a cost: long periods out with stress fractures and Achilles problems. His career shows both how far aerobic volume can take a runner and how hard it can be to sustain.

The edge. A base of aerobic volume built over years that let him win Leadville by more than an hour and a half on his first attempt.

What you can learn from Anton

1. Aerobic volume is still the foundation

Krupicka's results came from years of easy, high-volume running in the mountains. You do not need anything near his mileage, but the principle applies at every level: most of your running should be easy and aerobic, and gradually increasing that volume over months and years is still the most reliable way to improve at long distances.

2. Build volume slowly and respect the warning signs

His career was interrupted for years by stress fractures and Achilles injuries. Increase your training gradually, take pain in bones and tendons seriously, and build in easier weeks. The best training is the training you can keep doing.

3. Spend time in the mountains, not just training in them

Much of his running was exploring ridges and peaks rather than following a plan. Days out in the mountains, with scrambling, route-finding and long climbs, build the confidence and movement skills that make racing on technical terrain feel natural.

4. Keep it simple

His minimalist approach to shoes and gear was part of his identity, but the deeper lesson is simplicity. A consistent routine of easy running, regular long days and time on steep ground will take most runners further than complicated plans they cannot sustain.

Selected results

Year	Race	Result
2007	Leadville Trail 100	1st (second consecutive title)
2006	Leadville Trail 100	1st (17:01:56 on his first ultramarathon)
2014	Lavaredo Ultra Trail (118km)	1st
2021	Leadville Trail 100	3rd (17:07:55, first ultra since 2015)
2010	Miwok 100k	1st

A selection, not a complete race history.

Official profiles

Compare yourself with Anton

ITRA index calculator: estimate the km-effort and an indicative performance band for your own race result (not an official ITRA Performance Index).
Trail pace calculator: turn your road pace into a trail pace and finish time for a given elevation profile.

Frequently asked questions

How many times has Anton Krupicka won Leadville?

Twice, in 2006 and 2007, the first of them on his debut ultramarathon at age 23.

Why is Anton Krupicka known for minimalist running?

In his early and mid-twenties he trained on very high weekly mileage in minimalist shoes and often raced shirtless with long hair, an image that became closely associated with the early 2010s ultrarunning boom.

Runners with a similar profile

Jim Walmsley (United States): The first American man to win UTMB, and the athlete who redefined how fast a 100-miler can be run from the front.
Katie Schide (United States): UTMB course-record holder, Western States champion, Hardrock record-breaker and world champion over 82km.
Ruth Croft (New Zealand): The first woman to win the OCC, the CCC and UTMB: the complete Chamonix set.
Blandine L'Hirondel (France): A practising OB-GYN who became only the second athlete to win the OCC, the CCC and UTMB, after two Trail World Championship titles.

Sources and verification

Checked against the following sources on 2026-08-27:

Canonical page: https://trailia.run/best-trail-runners/anton-krupicka

Published by Trailia (https://trailia.run), a personalised trail running coaching platform. This profile is a factual reference, not a ranking.