Dina Asher-Smith has sounded an ominous warning to her rivals by revealing her love of sprinting is fuelled by the purest need for speed.

The 200metres world champion revealed her quest to find her full sprint limits "just never stops", in an engaging Instagram Live chat with former England Women footballer Alex Scott.

Asher-Smith set a new British record 21.88 seconds in storming to world championships 200metres victory in Doha in October, to cement her status as one of the globe's sprint queens.

And now the 24-year-old has conceded she expects to keep on running, long after her elite career is at an end.

Asked if she has ever had moments where she considered quitting athletics, Asher-Smith replied: "No, I never thought about quitting, never ever.

"I run for not just championships; I run just because I want to see how fast I can go, and that journey just never stops.

"I'll probably still run when I stop being elite, just because of how much I enjoy it."

In a wide-ranging discussion, Asher-Smith revealed her pride over having her own Barbie doll and the surreality of life as a role model.

Encouraging young girls to stick with sport through their tricky teenage years, Asher-Smith said: "There are so many reasons why young girls drop out, and I'm very passionate about keeping them in sports.

"Lots of people have anxiety when it comes to puberty. Because it's a time when people are trying to figure themselves out.

"When they look at what they see in the media, and while that's definitely changed a lot in the last three to four years, there are still many ideas of femininity that are sometimes at odds with the stereotypes of sportswomen.

"And there are pressures from elsewhere that tell them 'is it cool'.

"I tell them 'yes it's cool', but also people feel a bit embarrassed when they start to get boobs, to feel a bit uncomfortable.

"But just go and get a sports bra please because you will feel 100 per cent better. It transforms your experience.

"And some girls say they don't want to exercise on their period. But I would say no, it helps if you exercise during your period.

"And you have to be honest as well because if you're lying, people know.

"If you go into schools, athletics clubs, sometimes people ask you difficult questions that are tough for them to express.

"So you have to be honest because it's often things they feel they can't talk to their friends about.

"Quite often when you're honest with people, people are honest back. So often they will tell you things they are honest about when they perhaps haven't even told their parents or friends.

"And so you have a big responsibility to be honest. Because people are being really honest with you as well."

Barbie creating a custom Dina Asher-Smith doll left the 24-year-old stunned, and she explained how she continues to be surprised by her position as a role model.

"I'm so honoured, it was amazing when Barbie approached me about that," said Asher-Smith.

"It was definitely a special moment when they said they wanted to make a special doll of me.

"When we were growing up there weren't Barbies that looked like me. I didn't play with dolls that looked like me when I was growing up.

"When you're growing up, still figuring out where you stand in society, with your friends, that can be a bit weird sometimes.

"At stages you don't notice and at others you do. So the idea there's a doll that looks exactly like me now is really, really cool."

Asked how she reacts when people say she is a role model, she continued: "It's lovely, but it's a really weird thing to get a hold of.

"You're just doing you and doing what you've always been doing.

"Obviously we're just working at it. You're just doing something you're passionate about and it's your job.

"So hearing that, it takes you out of the bubble a bit. Because you say, 'really, but for what?'"