The most incredible athletes you've never heard of

Who has won the most ultramarathons, Ironman triathlons or achieved the most incredible endurance feats? Who is the fittest, toughest and most mentally strong human on the planet?

Mark Allen

  • Allen won the World Champion Ironman triathlon six times. The event includes a 2.4 mile open water swim, a 112 mile bike ride and a full-length marathon.
  • He also won the World Champion Ironman triathlon five times in a row from 1989 to 1993, setting a world record of 8 hours and 7 minutes that was unbeaten until 2011.
  • Best nickname in the sport: The Grip, as in, 'of death'.

Pam Reed

  • Pam Reed is one of the few women to win an ultramarathon outright.
  • She won one the Badwater UltraMarathon which is made up of a 135-mile run through Death Valley in temperatures of 50 degrees Celsius. Pam finished five hours ahead of her nearest male competitor.
  • The 5 foot 3 inch tall mother-of-five was 41 when she won the Badwater in 2002. For good measure she won it outright again the next year.
  • Reed once completed a 300-mile run without sleep.

Scott Jurek

  • Scott Jurek has had a huge cultural influence on the sport with a New York Times bestselling book Eat and Run promoting his vegan philosophy.
  • He is one of the most popular ultramarathon runners and has a huge Facebook following.
  • Despite winning the Spartathlon three times in a row and the Western States 100-mile run six years in a row, Jurek has a light-hearted approach to running: screaming at the beginning of each race, rolling over finishing lines and staying behind for hours to cheer late finishers.

Chrissie Wellington

  • In a big shock to the sport British athlete Chrissie Wellington won the 2007 Hawaii Ironman triathlon on her first attempt. She then continued winning the next three world championships she entered.
  • Wellington holds all three Ironman triathlon record times as well as the next four fastest times.
  • She only started running in her mid-twenties as a way to lose weight. She also overcame a major bike crash before her 2011 championship and in 2008 she still won despite losing ten minutes because of a flat tyre.

Yiannis Kouros

  • Kouros holds all the world records from 100 to 1,000 miles and from 12 hours to six days.
  • He ran 100 miles in 11 hours 46 minutes and 186 miles in one day.
  • He has been nicknamed "The Running God" and "Pheidippides' Successor". Read our guide to the world's most extreme races, including the Spartathlon where Yiannis Kouros first made his name.
  • Watch Kouros discuss the meaning of ultra running and his secrets: "you are clinically longer in control".