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Top 10 toughest ultra running races in the world

Written by Fiona

October 05 2021

A scientific study claims to have created a list of the top 10 toughest ultra running races in the world. Rokman, a virtual running challenge brand, supported research to analyse information, such as distance, elevation gain, temperature and energy expenditure. The list of the hardest foot races on earth was then compiled.

World’s toughest ultra running races by distance

Two race top the distance charts, including the six-day 380km (236 miles) Dragon’s Back Race in Wales and the non-stop 240-mile Moab 240. Meanwhile, the Wild Horse 200 (miles) also takes place in Wales and is another non-stop race.

Montane Dragon’s Back Race. Credit: No Limits photography

World’s toughest ultra running races by elevation

The Tor des Geants is a mountainous French race. (The race name translates as the Tour of Giants.) Runners on the non-stop course have to climb a massive 24,000m of total ascent.

In second place is the Dragon’s Back Race, which has a total climb of 17,400m, while the notorious Barkley Marathons has 18,288m of ascent (if runners actually complete it).

Read about: Ultra runner Nicky Spinks in the Tor des Geants 2021.

Marthon des Sable. Credit: Kaisove

World’s toughest running race by temperature

The top three races with the highest temperatures, according to the research, are Badwater 135, the Marathon des Sables and the Everest Marathon.

World’s toughest running race by energy expenditure

The researchers looked at calorie burn in the overall races and listed the top three as the Tor de Geants, Dragon’s Back Race and Moab 240.

Top 10 world’s toughest running races

In the end, it was analysis that focused on calories burned per mile that was used to assess the world’s toughest foot races. While not the longest race, The Barkley Marathons sees runners burning an average of 162 calories per mile. Next came the Tor des Geants, followed by Badwater 135 in third place. 

  1. The Barkley Marathons (162)
  2. Tor des Geants (153)
  3. Badwater 135 (149)
  4. Hardrock 100-Mile Endurance Run (136)
  5. Hurt 100 Trail Run (129)
  6. Ultra-Trail du Mont Blanc (128)
  7. Pikes Peak Ascent and Marathon (128)
  8. Dragons Back Race (117)
  9. The Plain 100 (114)
  10. The Eastern States 100 (113)

Rokman founder, Terry Rosoman, said: “Obviously, this is just a theoretical data study, however, it’s great to get some way towards finding the world’s toughest race once and for all. 

“I hope it sparks a dialogue between people to further discuss their thoughts, feelings and experiences on which race they believe is the toughest in the world.”

For more details about the research.

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