In 2011, student Naufal Ali often slacklined alone in the void deck of his Housing Board flat in the middle of the night. Like tightrope walking, slacklining involves balancing and walking on a line anchored on both sides above ground level.
Mr Nauful, now 25, would attach a slackline to two pillars and do tricks on it.
Once, he botched a backflip, hit his head on the concrete floor and suffered a concussion. He had to be hospitalised.
Such experiences have led slacklining enthusiasts to stress the importance of safety to newcomers as it grows more popular here.
In 2010, when slacklining was introduced to Singapore by a few enthusiasts, only five people were known to practise it.
A year later, these slackliners brought in Elephant Slacklines, a franchise of slacklining equipment from Germany, and started showcasing the sport in schools.
Now, there is a community of more than 1,000 enthusiasts here.
The sport was invented in the 1970s by rock climbers in the United States. Practitioners walk on a line made of nylon webbing that stretches and feels slack when walked on, hence the name of the sport.
Slackliners say the sport improves their balance and concentration and they relish the excitement of walking or performing stunts on a line.
In 2013, a group here worked with *Scape to start a weekly three-hour slacklining session at the youth hangout. These free sessions are ongoing and held on Mondays at 7pm. At these sessions, there are safety mats on the floor and experienced slackliners such as Mr Naufal on hand to provide guidance for newcomers.
Other slackliners have also held gatherings at places such as East Coast Park and West Coast Park.
Prominent events, such as the Singapore Night Festival and Adult Playground sports and music event in 2014, have also featured slacklining demonstrations.
Katapult Trampoline Park in Yishun, which opened last July, has a slacklining zone with two 6m-long slacklines.
New fans of the sport include Ms Deborah Wong, 26, an operations manager in a genetic testing company, who chanced upon it during the Singapore Night Festival in 2014.
She says: "After giving it a try, I think it helps me focus better and get in tune with my body."
Soon, she began attending the weekly slacklining sessions at *Scape and can now balance and perform various yoga poses on a slackline.
Another fan is Mr Heng Yongli, 26, an economics and management undergraduate, who started attending the weekly sessions in 2013. He was intrigued after watching YouTube videos of famous slackliners, such as Brazilian Carlos Neto and American Andy Lewis, performing somersaults, flips and twirls in mid-air.
Says Mr Heng, who can do chest bounces on the line and simple turns mid-air: "I hope to be like them and bounce on the line as if it is my own trampoline. That would be so cool."
Avid rock climber Akid 'Ammar, 22, picked up slacklining in 2013 as he felt it was a natural extension of rock climbing.
He says: "It helps me better distribute my weight, maintain my balance and be focused."
When he first tried walking on a slackline, he fell off about 100 times. Now, he can walk 40m on one without falling.
"Initially, I saw the line as a small piece of hard floor or a log. I was wrong. To balance on the line, you have to be one with it. And when you do, it feels like you are walking on air."
Despite the assurances given by the slacklining community here, some still have safety concerns.
Trampoline park Zoom Park Singapore in Pandan Gardens used to have a slackline, but its co-founder Vik Waran decided to take it down because he feared customers might get injured.
Says the 38- year-old: "Nothing serious happened, but I saw children slip while jumping on the slackline.
"My advice to anyone wanting to try slacklining is to start slow and always make sure safety comes first."
See some of the "tricks" of slacklining http://str.sg/43Cs