Two sisters' 40-hour bike trip from Ho Chi Minh City to Hanoi has prompted others to challenge themselves by completing the route as fast as possible.

Vietnamese sisters Thien Thu and Thien Thuong have found themselves in the social media spotlight since they announced their 40-hour Ho Chi Minh City-Hanoi bike trip.

To put their journey into context, the fastest trains between the two cities take approximately 31 hours to complete the 1,730-kilometer journey.

“We conquered the route once before in a group of 20, and it took us 48 hours,” Thu said. “Our goal this time was merely to see if we could beat that time. That’s why we didn’t stop on the way for sightseeing.”

The sisters said they did not encounter any problems during their 40-hour bike trip, and described their feeling upon reaching Hanoi in record time as one they “wouldn’t trade for the world.”

“Impossible things are being done all the time by people around the world, many of whom are women who are too often stereotyped as weak and vulnerable,” Thu said in response to skeptics who questioned the authenticity of their story.

However, their seemingly impossible feat has inspired a trend among other young adventurers in Vietnam, who are challenging themselves to complete the route in the shortest possible time.

Shortly after the girls published their story, two young men came forward on social media, claiming they had traveled by motorbike from Ho Chi Minh City to Hanoi in 28 hours and 35 minutes.

The duo kept friends updated on their progress by posting photos of the places they passed on Facebook, starting from 8:00 pm on February 27 to 35 minutes past midnight on March 1.

Irrespective of whether their story was true, many have already pointed out the danger they would be putting themselves and others in if they did in fact travel at such a fast pace without sufficient rest.

To complete 1,730 kilometers in 28.5 hours, the duo would have had to travel at an average speed of over 60 kilometers per hour. In reality, they must have traveled even faster while on the move to make up for time spent resting.

Vietnam’s traffic laws state that motorbikes are allowed to travel at up to 60km/h on streets that have permanent lane separators; and 50km/h on those that do not.

“Some youths use excuses for pushing themselves to the limit and following their dreams, but I have to disagree,” said Pham Mai Huong, 26, an experienced traveler. “There are many other ways to fulfill one’s dream without putting your life and the lives of others at risk. If you want to race then take it to a racetrack; don’t race on the highway.”

Huong said the most important aspect of a trip in her opinion was to explore the world and find one's limits through the adventures and challenges that follow.

“I won’t set a goal for myself to be the fastest or to go to as many places in the shortest time as possible just to brag about it on social media,” Huong said. “Instead of checking in, I think the time would be better spent exploring the local culture and the people of the places you pass.”