Miss Sandra Riley Tang, 26, one-quarter of popular local pop band The Sam Willows, is able to grapple, choke and overpower a guy who is much bigger than her.
It helps that she has a blue belt in Brazilian jiu-jitsu (BJJ), a martial arts form that focuses on grappling and ground fighting.
"I've always liked martial arts. You get to hit things and kick things. It sounded like fun and is a good skill to have," she said.
"When I first saw BJJ, I was like: 'Go punch someone, come on, do something, why are you on the floor?'"
She started doing muay thai or Thai kickboxing, but became hooked on BJJ.
When I first saw BJJ, I was like: 'Go punch someone, come on, do something, why are you on the floor?' It's really something that was absolutely new to me. The more you practise, the more combinations you learn. It's like a chess game.
MISS SANDRA RILEY TANG, The Sam Willows band member, on Brazilian jiu-jitsu.
"It's really something that was absolutely new to me. The more you practise, the more combinations you learn. It's like a chess game," said Miss Tang.
Like her, more and more young people are hooked on fighting as a form of fitness.
People have been doing martial arts for years but, in recent years, it is largely BJJ, muay thai and mixed martial arts (MMA) that have become trendy.
MMA combines combat sports from around the world. It can involve a striking discipline like boxing or muay thai, and grappling sports like wrestling and BJJ.
Mr Chatri Sityodtong, owner of a chain of Evolve MMA gyms, said his clients range from chief executives and doctors, to teachers, nurses and engineers, to students.
Although martial arts training attracts mostly men, more women as well as some children and older adults are also signing up.
"When we started, about 10 per cent of our clients were female. Now, there are more. Some days, we may get 60 per cent men and 40 per cent women," said Mr Arvind Lalwani, who owns Juggernaut Fight Club in Hong Kong Street.
The credit for the rising popularity of MMA goes to its promoters, the biggest of which is the US-based Ultimate Fighting Championship (UFC), staging fights that draw crowds of at least several thousand people.
UFC, which is open to only elite fighters, will be returning to Singapore on June 17 after a three-year absence.
Mr Sityodtong is also the chairman and founder of Asia's largest MMA promoter, One Championship. Established in Singapore in 2011, it snagged an undisclosed eight-figure sum from a consortium led by a Temasek Holdings unit last July to expand in the region.
There are also smaller events like the Singapore Fighting Championship, an amateur MMA organisation that was founded in 2014.
Today, Evolve MMA has three branches, at Far East Square, Orchard Central and PoMo in Selegie Road. It has 50 instructors and is in the midst of hiring more as it expands, said Mr Sityodtong.
Over at Juggernaut Fight Club, Mr Lalwani said classes used to draw 30 to 40 people a day, but now, there can be 60 to 80 people. The attraction of these martial arts is that they can teach one to fight, but for those who are not ready, at least one gym, FaMA, offers fitness training with some martial arts moves.
Depending on the intensity, the classes focus on body weight drills and coordination exercises, or circuit training, but always with martial arts moves from BJJ and muay thai thrown in.
These fitness classes will help improve a person's overall physique, stamina, functional strength, balance and flexibility, said co-founder Bruno Amorim, who holds a black belt in BJJ and is a professional MMA fighter.
Mr Hiroshi Yamada, 29, who trains in muay thai, said what he liked was the opportunity to train under world champions.
Mr Yamada, who weighed more than 95kg at one point, said the sport helped him shed 25kg. He was also inspired to change his diet and lifestyle.
"Muay thai is a fantastic cardio workout. In a one-hour class, I can burn up to 1,000 calories," he said.
More than that, muay thai has taught him respect, confidence and discipline, he added.
RISKS AND REWARDS
As for the safety of martial arts training as a form of fitness, sports doctors say that as long as it is a combat sport, there will be an inherent risk of injury.
Also, some martial arts forms are riskier than others.
Dr Cormac O'Muircheartaigh, a sports medicine physician and director of Sports Medicine Lab in Tanjong Pagar, said more people are seeking help for injuries such as lacerations and fractures sustained during martial arts training, especially in the last two years, about the time that the sport had become popular.
"If you like the idea of combat sports, but are not prepared to take the inherent risk, then don't do MMA," said Dr O'Muircheartaigh.
He recommends doing BJJ just for self-defence, as the risk is less than that for a striking sport like muay thai and boxing.
Dr Fadzil Hamzah, a staff registrar at Changi Sports Medicine Centre, said MMA is possibly one of the safest full-contact sports today, because it targets the whole body, though research is limited.
"Strikes in MMA are directed at all parts of the body. In boxing, strikes are largely directed at the head, and it is the accumulation of those blows to the head that is devastating," he said.
Ultimately, those who train in martial arts will not only develop authentic self-defence skills, but also more courage, discipline, focus and mental strength.
For those who say that MMA or martial arts is more for men, at least one gym offering martial arts training to men and women - Trifecta Martial Arts - was started by two women three years back. One of the co-founders had said she took up BJJ after an abusive relationship, during which her former partner once threw a bedside table.
Being empowered is important, said Miss Tang, who picked up BJJ about two years ago and does it about two to three times a week, for up to 1½ hours each time.
"And a woman who can fight is definitely sexy," said Miss Tang, who also does yoga and strength training, and has competed in BJJ.
She said she had not suffered any injury, though she had her contact lenses knocked out by her opponent during her first competition.
"Fighting, it builds your confidence and it's important for women to be able to fight and save themselves if needed," she said.
If you want to learn how to fight...
With combat sports like muay thai or mixed martial arts (MMA), there is an inherent risk of injury.
For instance, in muay thai training, one can kick someone's arm instead of the pad, due to either fatigue or poor technique.
Or in Brazilian jiu-jitsu, a new participant can end up with a broken arm or other injuries as he may not know when to tap out in order to get his opponent to stop.
"Inexperience means it is easier for an opponent to get you into a vulnerable position and further inexperience may stop you from tapping out, until an injury is sustained," said sports medicine physician Cormac O'Muircheartaigh.
Dr Fadzil Hamzah, a staff registrar at Changi Sports Medicine Centre, said older adults with cardiovascular risk factors or symptoms suggestive of cardiovascular diseases should get a pre-participation screening before engaging in a physically demanding sport like MMA.
Here are the physicians' tips for those who are new to martial arts training:
DO YOUR RESEARCH
Talk to people in the industry to find out more about the sport and go for free trials at different gyms, said Dr O'Muircheartaigh, who is also the medical consultant in Asia for the Ultimate Fighting Championship.
MMA is considered one of the hardest sports to train for.
If you want to be an MMA fighter, join a professional MMA gym that has experts who will guide you along with a customised training programme, said Dr Fadzil, who was the chief medical director for ONE Championship. "The worst thing you can do is to do pointless workouts on your own that are based on a generic exercise programme that you found on the Internet."
Bodies adapt to what they are put through. Build up your skill level gradually as this has been shown to reduce injury rates, said Dr O'Muircheartaigh.
"There are no shortcuts in learning new skills in any sport and unless you get the fundamentals right and master the basics of a discipline or sport, you are at a higher risk of injury and poor performance."
Dr Fadzil said many athletes rely solely on high-intensity interval training, as many fitness experts and conditioning gurus claim that slower endurance training will cause one to lose muscle and strength. He counsels otherwise, as a well-rounded training is the way to go.
COMPETE ONLY WHEN YOU ARE READY
Many amateur athletes often try too hard and rush their progress. "You cannot be an MMA fighter in a week," said Dr Fadzil. "This is going to take years and years of developing your skills."
You must also gradually strengthen your body.
Said Dr O'Muircheartaigh: "If you are experienced in one discipline but not in other areas, these weaknesses will be exploited by an experienced opponent. This will increase the risk of injury (and losing in a competitive environment)."