Doha - Caster Semenya won the 800 metres at the Doha Diamond League meeting on Friday in her first race since losing her appeal over a controversial gender ruling, claiming "actions speak louder than words".
The South African, a two-time Olympic champion, timed 1:54.98 to defeat Burundi's Francine Niyonsaba, who clocked 1:57.75 and Ajee Wilson of the United States in 1:58.83.
Semenya's victory could be her last over 800m before new IAAF rules governing testosterone levels come into operation on May 8.
However, asked if she intended to take hormone-suppressing treatment, she said: "Hell no. No way.
"I don't know what will happen next. But no-one should tell me what to do, if people want to stop me from doing something that's their problem, not mine."
After setting a new meet record, she told the BBC: "Actions speak louder than words. When you're a great champion you always deliver.
"With me, life has been simple. I'm just here to deliver for the people who love and support me. I'm enjoying each and every moment of my life maybe because I have the love I need from my people."
Semenya, 28, was only added to the 800m start list in Doha on Thursday morning, a day after her appeal against a new rule regulating testosterone levels for women athletes was rejected by the Court of Arbitration for Sport (CAS).
She had challenged the measures, introduced by the IAAF, that will force women with higher than normal male hormone levels - so-called "hyperandrogenic" athletes - to artificially lower the amount of testosterone in their bodies if they are to continue competing.
The rules will come into effect on May 8 and will apply to athletes competing in races over distances of 400m to the mile.
Semenya hinted at quitting the sport in a tweet on Thursday, saying: "Knowing when to walk away is wisdom. Being able to is courage. Walking away with your head held high is dignity."
After her win on Friday - in the same city where she hopes to feature in September's world championships - Semenya said she was fighting a bigger battle beyond the track.
"This is all about inspiring the world. This is more than a game, more than sports. This is about human dignity, human pride. What you do if youre inspiring the world.
"People fight me, I don't fight them. I live life and I enjoy it.
"In September, of course, my main goal is to defend my title! But I am a crazy athlete, who goes from one race to another (from 400m to 5,000m) and I will continue.
"It was an incredible race tonight, I worked hard. I felt great, I am very happy. I did what I came to do.
"1min 54sec is a very good time. Now I will go home and train hard to do better than 1.54."
Aleck Skhosana, president of Athletics South Africa, told AFP in Johannesburg that Semenya's performance had put her critics firmly in their place.
"We are excited that Caster has done what she is known for ... despite all the challenges that she is facing," said Skhosana.
"We encourage her to stay focused and do what she does best - which is to run and conquer the world."
Elsewhere on Friday in the Qatari capital, Britain's Dina Asher-Smith cruised to victory in the 200m.
The European champion won in a season-leading 22.26sec ahead of Jamile Samuel of the Netherlands and Nigerian sprinter Blessing Okagbare.
Kenya's Elijah Manangoi won the men's 1500m, holding off a late charge from training partner Timothy Cheruiyot to win in 3min 32.21sec.
Hellen Obiri also starred for Kenya with the world cross country champion powering home to win the women's 3000m in 8min 25.60sec.