Or to put it another way, imagine running in just over a day from Ho Chi Minh City to Mui Ne. That is what he did on September 30.

One of the most celebrated long-distance runs in the world, the Spartathlon traces the footsteps of Pheidippides, an ancient Athenian runner who in 490 BCE was sent to Sparta before the Battle of Marathon to seek help in the war against the Persians.

Ancient Greek historian Herodotus wrote that Pheidippides ran the whole distance and finally arrived in Sparta a day after leaving Athens.

Quang is the first and only Vietnamese to have completed the race.

"It was really the most difficult race I have run. It is the longest distance I have ever run, and the cut-off time was short. Not only was the distance a big challenge, the weather was also very different from what I expected," he told VnExpress International.

He had trained for about three months, clocking 120 km a week in Ho Chi Minh City where he currently lives, and in the mountains in the nearby Ba Ria-Vung Tau and the Central Highlands' Da Lat. But that was not enough. He said he should have trained longer and the locations were not very good either.

"The weather conditions in Da Lat were also different from Sparta. Sparta was hotter and sunnier than Da Lat during the day, with the temperature at around 35 degrees Celsius and colder than Da Lat at night, with temperatures of 10-12 degrees Celsius."

He also noted the pros and cons of doing training runs in Vietnam's largest city: "In Ho Chi Minh City, the jogging movement is very developed; there are many active running groups. However, the traffic is very thick and the air is not fresh."

But he was relieved, elated, relaxed, and filled with a tremendous sense of satisfaction to have completed the race.

"Completing such ultra runs is great, it really builds my mental strength and I love challenging myself to overcome obstacles. I also want to show Vietnam to the world through my ultra-running."

Tran Duy Quang poses with Vietnam's national flag after finishing
the ultramarathon Spartathlon in Greece, September 30, 2019.
Photo courtesy of Tran Duy Quang.

He has achieved so much as an ultra-distance runner but what got him started?

"Work stress!" He laughed.

While working at Pepsico in Bien Hoa near HCMC five years ago, he wanted to find a way to deal with the stress at work and started running regularly. The physical exercise, relief and mental strength he got from long-distance running became a natural spur, and the more he did it, the better he became.

Before he knew it, he had signed up for the 2015 Vietnam Mountain Marathon in Sa Pa in the northern highlands, and completed the 42km. He soon decided to do a 100 km run on his own from Quy Nhon to Tuy Hoa along the south central coast in 2016.

He registered for the 2016 Vietnam Mountain Marathon 100 km ultra race and finished 4th. In 2017 he entered again and this time won it in 13 hours 17 minutes, becoming the first Vietnamese winner.

One of the most difficult race he has participated in was the Ultra Trail du Mont Blanc in August 2018. Runners had to run through three countries, France, Italy and Switzerland. He was alone in the mountain one night, and the weather was bitterly cold, but somehow some inner reserve kept him going.

In the space of five years the 30-year-old has become an inspiration to many.

People close to him get inspired and run every day, while all his colleagues at his current company, biotechnology firm Genetica, started running when he set up a Group Run. His colleagues usually do one weekly running session and some of them are also participating in the Vietnam Trail Marathon in January 2020 in Moc Chau in northern Vietnam, registering for distances from 21 km to 70 km.

On his Facebook fan page, "Quang Tran Ultra Runner," he currently has more than 1,400 followers.

"Running helps me be healthier and more optimistic. It also helps me meet more interesting friends and explore more places around the world," he said.

He has a simple piece of advice for all ultra-distance aspirants: "Listen to your body, train a lot and enjoy it."