Deep down, sport is all about emotion and when Laviai Nielsen crossed the line at the 2019 Muller Anniversary Games, everyone in the Olympic Stadium was reminded of that fact.

Even cloistered away in the mixed zone, I could feel the delight ripple around Stratford as Nielsen - by now cradled by Emily Diamond - realised that she had finally broken 51 seconds. It was the second time in July alone that the London-based sprinter had lined up against a world-class field; grabbed the occasion by the horns and produced her fastest time in 2019.

Her highlight reel performance has thrust her into a spotlight that, in truth, should long have dwelled on her incredible talent around the quarter-mile. In front of the BBC cameras, it was simply vindication for a season of self-improvement of which I was well aware when I sat down with Nielsen earlier in the month.

Considering the 23-year-old brands herself as a coffee lover in her Twitter bio, it was perhaps fitting that we discussed all things athletics in the local Costa at Lee Valley. It was clear even from then that the Olympic Stadium meant so much to Nielsen - from famously being a kit-carrier for Dame Jessica Ennis-Hill to being crowned a World medalist just half a decade later.

Discussing that triumphant moment, Nielsen spoke of an innocent conversation that would ultimately light the touch paper for global success - explaining: "When I was 16, I remember turning to my sister and saying: 'the World Championships are here in five years, we should probably do something about it!' But it was one of those things that you just say and don't really expect.

From London 2012 to London 2017

"It was so far-fetched from where we were. We were 16 and we were athletes, but we were very much below average. So, we kept progressing year after year - I think it was the year after we decided to move to 400m - and it just snowballed into what it became.

"I just remember when the anchor leg crossed the line, thinking: 'as if I've got a medal here, when I literally witnessed Super Saturday,' it was so special. I literally couldn't stop crying afterwards. It really was a dream come true." No matter what Nielsen goes on to achieve, she will always treasure that relay silver and, like Saturday to Sunday, it was the perfect sequel to Ennis-Hill.

The legendary heptathlete to whom Nielsen stood just metres behind has always served as an inspiration, both in terms of her attitude on the track and away from it also. Of course, the sprinter has now had the opportunity to meet her hero and Ennis-Hill could even be seen commenting on her Instagram just this week: 'Bloody brilliant! Congratulations! I'll get sorted with a kit box as well!'

Inspired by Jessica Ennis-Hill

"Jessica Ennis. She's my biggest idol," Nielsen unabashedly replied when I asked about her sporting heroes. "I do see a lot of myself in her. Growing up, some of the biggest male role models were David Beckham, Roger Federer and Andy Murray. It was mainly male athletes that you'd see on the front page of newspapers and then all of a sudden, there was a woman of such calibre.

"After seeing her in 2008, I remember the injury like it was a few years ago, and seeing her turn around from that to win the World Championships the year after, I remember watching that on the TV and thinking: 'she's actually incredible.' She's just such a great example of perseverance, grit and she's just such a great person as well - she's so lovely.

"I've met her now a couple of times and I still look at her and think: 'You're unreal! You're actually an insane person.' That's the kind of person I aspire to be. Not just as a performer - I tried the heptathlon and wasn't very good at it - but as a person and a role model as well."

Partners in crime

Of course, Laviai certainly isn't the only Nielsen in athletics. Her twin sister, Lina, has also strode spikes-first into the world of athletics and, with the same symmetry that saw them garner identical exam results, sprinting was the event of choice. There are so many clichés surrounding twins, but perhaps the Nielsens, with their special bond, are evidence for some of the most golden.

In a notoriously lonely sport, the sisters have one another for support on the toughest of days, even if Laviai never loses that drive to wake up and attack the track. "It helps having my sister in the sport as well," the 23-year-old explained. "We literally do the same thing, we've got the same interests, we love the sport very dearly the both us, so it's really special to have her in the sport.

"It makes me feel less lonely. If she wasn't in the sport, I wouldn't be in the sport and she would say the same thing. When we were younger, we were literally the spitting image of one another - I would do what she wanted to do and she would do what I wanted to do. We had the same GCSE and A-Level grades, we were literally that similar!

"We train separately now, but we live together and we enjoy the sport together. We watch all of the athletics together, and we know everything that's going on. It just makes it so much more enjoyable because you're doing it with your best friend. The best way I can describe it is: you know when you drag your friend along to something and it's much more fun? That's what it's like to have Lina there."

Inspiring the next generation

Climbing through the ranks, Nielsen has been able to look up to athletes like Ennis-Hill, while also having Lina by her side, but the Brit has quickly become a role model of her own. Athletics is blessed with its equality compared to other sports and Nielsen now has a platform to pass on wisdom to young girls and boys from a myriad of backgrounds.

From reiterating that it's what your body can do, as opposed to what it looks like, that counts and joking that childbirth is the 'secret' for athletes like Shelly-Ann Fraser-Pryce; Nielsen slips into the 'role model role' with ease. The World medalist revealed: "I have young athletes messaging me saying: do you do this kind of session? What do you do with a race like this coming up?" 

"To be able to share my thoughts and experiences with those young athletes is so incredible and shows that 'real' side of the sport. I get a lot of questions about sports psychology, which is a lot more open these days, if people are struggling with race-day nerves and the mental side of the sport. It makes things more open and I hope it keeps young girls in sport.

"I think it's one of the positives of social media. I try and share as much of my training as I can because when I was growing up, if I'd have known what Jessica Ennis was doing in training, that would have been amazing - I would have killed for that!" It's a cycle of sporting inspiration, of which Nielsen is truly a part, that brings us back to 400 metres of polyurethane in Stratford. 

From London to Doha?

The Olympic Stadium has always been a cauldron of sporting memories in the world of athletics. The whole meaning of the Anniversary Games and the legacy of London 2012 are both sentiments that have been channelled into existence by athletes like Nielsen. It did, after all, host that moment of inspiration that would take her to World glory and PB's on the very same plot of land.

Whether or not you believe in fairytales in sport, you can't deny that things have worked out with a certain poetry. However, the real dream is thousands of miles away in 2019 and Doha awaits for the finest athletes in the world to hold themselves to the mark. For Nielsen, there's the chance to grab the rhetoric of 'Inspire a generation' from the London hoardings and stake it in the ground of Qatar.

That, or a little kit box - perhaps one worthy of Ennis-Hill - filled with a global medal and 50.83 seconds of pure delight.