Menstruation has brought other unexpected challenges for Issey, too. On one occasion, while warming up for a race around the time of her period, she uncharacteristically smacked her knee on a hurdle. “The same thing then happened in the actual race, after the warm-up, and it happened again recently in a training session,” explains Issey. “Maybe there’s some sort of science behind it, but we don’t know because we couldn’t find any information about it.”

Scott nods his head in agreement, and begins recounting one scenario where he desperately sought out advice from other parents trackside as to whether his daughter should compete while on her period. “It’s almost as if there’s a lot of issues and no solutions,” he sighs. “There’s certainly no handbook, that’s for sure.”

It is a bleak assessment, albeit one that tallies with how the majority of sports science has historically been skewed towards men. Even when women are included, 70 per cent of research engages women as subjects to study when their hormones are at their lowest point in their menstrual cycle – in order to more closely resemble a male body.

Dr Emma Ross, one of Britain’s leading sports scientists who co-founded The Well – a platform dedicated to championing female physiology to help close the body literacy gap in sport – points to one theory which might explain Issey’s clumsiness when hurdling before her period. It concerns progesterone – the female sex hormone that peaks just before menstruation – which can influence parts of the brain that govern motor control, including a person’s co-ordination. “But equally, the way her body is changing means that her centre of gravity might have changed. That will affect how she goes about getting over the hurdles,” adds Dr Ross.

She also says that Issey’s extreme hunger patterns are not unique. “When a girl starts her period, it’s the first time in her life that she has these peaks and troughs of oestrogen and progesterone and these female sex hormones drive changes in behaviour and appetite and can impact metabolism, blood sugar stability,” explains Dr Ross. “If your blood sugar is less stable, you can get more cravings or hunger – coupled with the fact teenagers are going through a huge growth phase, which takes loads of energy.”

The knowledge gap in female athlete health is often exacerbated by athletics’ staunchly male coaching force, where there remains a reluctance to acknowledge the role periods might play in athletic performance.

Jarrett, the celebrated 110m hurdles champion who has been coaching Issey for the past year, believes that male coaches could benefit from an upskilling around female physiology.

“My senior athletes will come up and tell me it’s that time of the month – they might be feeling a bit tired – so we’ll tailor the session towards them. My younger female athletes don’t really say anything,” says Jarrett.

“Young girls do a lot sporting-wise at school these days – sometimes they can be lethargic – but I wouldn’t say, ‘Are you on your period?’ I’d just say, ‘How are you feeling?’ And if they’re not feeling great, we’ll take the session down. That’s something I think male coaches should be able to do, but we have been scared.”

Thinking of the next generation of young girls who will encounter the same challenges as Issey, what would her advice be on how to cope? “Listen to your body,” she says. “Don’t push yourself too hard and do all these crazy things because you think it will help you, and try to make any weight gain healthy.” She pauses, before remembering one of the many societal pressures imposing themselves on teenage girls. “Oh,” she says casually, “and do you have to have hairless legs? That’s just other people’s standards – just do you.”