For taekwondo exponent Chelsea Sim, it really is all about the heart.
At just 1.50 metres, the 19-year-old may look like a vulnerable sweetheart who loves shopping and TV series, but she wields a deadly kick that can reach a height of 1.80m.
Her agility and flexibility impressed many at the 2013 SEA Games, but controversy struck in the final when hosts Myanmar's Yamin K Khine was awarded almost half a point more than Chelsea.
That denied her the honour of winning Singapore's first SEA Games taekwondo gold since 1999 and left her heartbroken.
But she overcame her disappointment and persevered. Since then, she has won gold medals at last year's Asian Cities Gold Cup and this year's US Open taekwondo championships.
She will compete in the SEA Games poomsae women's singles and mixed pair events in Singapore next month.
Oh, and did we mention, she has accomplished all these feats with a hole in the heart?
Her elder sister Courtney has the same birth defect, although it is not hereditary. "If I over-exert, I will feel breathless and a tightness in my chest," Chelsea told The New Paper.
"But I know my limits and when to stop. Actually, ever since I picked up taekwondo, my immunity has improved and I have grown stronger."
The Singapore Management University business undergrad has also matured mentally and emotionally.
"I am no longer upset; I will use it as motivation," she said. "My goal is gold.
"My family and friends are excited because they have never seen me compete at a major competition, and they have bought tickets to support me."
A key figure in her corner is four-time SEA Games champion Wong Liang Ming, who is also the Singapore Taekwondo Federation secretary general and national team head coach.
"Coach Wong has been my coach for four years and she is like my second mother," said Chelsea.
"I see her more than my own mother because I spend eight hours at the federation and, after my real mum fetches me home, it's almost bedtime.
"Coach Wong travels with me for overseas competitions and has been with me when I lost and cried, or won and celebrated."
Wong, 52, hopes Chelsea can finally top the podium next month.
Targeting two gold medals, she feels that Team Singapore stand a better chance in poomsae than gyeorugi. Poomsae is a defined form of defence and attack motions, while gyeorugi is the sparring form.
She said: "It will be difficult for us in gyeorugi because our main rivals are the Thais and Vietnamese, who are full-time professionals and have height advantage over us.
"Thailand's Panipak Wongpattanakit just won the women's finweight (up to 46kg) world title this month, and is also the Youth Olympic champion. She is just 17, but is already more than 1.7m tall.
"But, as you can see from the 2013 SEA Games, poomsae is a very subjective discipline.
"We have talented poomsae and gyeorugi exponents, but most of them have to juggle school and training.
"So, as long as our athletes do their best, we will be satisfied."
This article was first published on May 26, 2015.
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