split image of John Young during ultramarathon

A Canadian man with dwarfism has been verified as the world’s shortest person to complete an ultramarathon.

58-year-old John Young, who stands at a height of 131.1 cm (4 ft 3.6 in), achieved the record by running the Ghost Train 30-Hour Ultramarathon in New Hampshire, USA.

He ran 31 miles (the minimum distance required for an ultramarathon) in 12 hr 9 min before stopping, averaging a time of just under 24 minutes per mile.

People with dwarfism take over double the number of steps to complete a marathon than average-sized people do.

John, who works as a maths teacher in Massachusetts, is one of just a handful of athletes with dwarfism to have ever run a marathon, and he is the only one known to have completed an ultramarathon.

John Young walking with other runners

John revealed that his preparation for the ultramarathon “wasn’t really a lot different” to his regular exercise routine.

He said: “I just continued to train like I have been for the past 10+ years: I bike, run or swim six days a week and I just continued to do so leading up to this race.”

John was born with achondroplasia, which is the most common form of disproportionate short stature and is the same form of dwarfism that the world’s shortest woman has.

He grew up in Toronto in foster care, and although he swam and played hockey as a child, doctors advised him against running because the impact on his spine could cause permanent back problems.

By the early 2000s, John had become dangerously obese for his height, weighing 195 lb (88 kg). He suffered from sleep apnea and was at risk for serious heart problems.

split image of John Young running

“I had spent most of the first 40+ years of my life listening to people who told me: ‘you’re too small to do that’ or ‘you need to be careful’ or ‘you might get hurt’,” John recalls.

“But then at the age of 43 years old, I stopped listening.”

John took up swimming and cycling and entered a triathlon, but he skipped the running section as he feared he might injure himself.

However, one day – against doctors’ advice – he started running and surprisingly discovered that the more he ran, the less his back hurt.

John hasn’t looked back since; to date, he’s run 21 marathons including the Boston Marathon and the New York City Marathon.

John Young with thumbs up

In addition to having also done 10 “Half Ironman” triathlons, in 2016 he became the first person with dwarfism to complete a full Ironman, which consists of a 2.4-mile swim, a 112-mile bicycle ride, and a 26.2-mile marathon run.

John followed up this feat in 2018 by running 12 marathons in 12 months. “The next logical step for me was to race an ultramarathon,” he said.

Although John is currently the only known person with dwarfism to have completed an ultramarathon, he may be joined in the near future by his adult son Owen, who also has dwarfism.

Owen is an equally keen runner and has already beaten some of his dad’s personal best 5K-run times. 

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