A keen marathon runner, Missouri woman Chau Smith wanted to challenge herself further and made the decision to run races in Perth, Singapore, Egypt, Netherlands, New York, Chile and Antarctica in seven days. That's seven full-length, 42 kilometre marathons run over a single week.
Completed between January 25 and January 31, Smith finished each race then flew to her next destination, with news of her achievement only recently coming to light as she did not want to publicise her effort, instead choosing to share her story after concluding the gruelling endeavour.
The Vietnamese-born Smith was joined by nine other people on the journey, with the adventure aptly named the Triple 7 Quest by Marathon Adventures owner Steve Hibbs who organised the trip.
In a video posted to her YouTube channel, she described her love of running and how her decision to take on the exhausting trip was done to celebrate her seven decades.
"I started running in 1990 to release stress and be healthier. I ran my first marathon six years later to raise money for Leukemia research," Smith says in the YouTube video.
"The reason I am running the Triple 7 Quest is that I'm turning 70 next month - I thought it would be a perfect challenge to run seven marathons in seven days on seven continents to celebrate my seven decades."
Speaking with CNN, the resilient 70 year-old said her most testing race was in Cairo after the group's flight was delayed, leaving her with only minutes to prepare.
"We have 10 minutes to go up to our rooms to change and don't unpack," Smith tells CNN.
"The key wasn't working for my room. I almost used up my 10 minutes. I was crying."
In order to ensure that they were able to retain the energy needed to complete all seven races, the majority of the runners had a set time to finish the race by. Normally given seven hours, the delay meant that the time was reduced to six, leaving Smith concerned that as the oldest runner in the group that she would not be able to finish in time.
After Hibbs suggested she run the half-marathon, she went on to finish the full race in five hours and 51 minutes, defying expectations about her age.
Born in South Vietnam, she emigrated to the United States in 1972 and having completed more than 60 marathons has now set her sights on completing the Appalachian Trail, a hike more than 3,500 km in the North East of the US.
She also tells CNN she continues to run because it makes her feel healthy and release stress.
"I live a stressful life. Every day, I work 10 hours a day... How I feel after I put in my running, I think that's important. It makes you feel good. I can't really put it into words."