Over the past eight years, West has noted more attention being paid to the correlation between quality sleep and elite sports performance.

In turn, athletes have developed heightened awareness, in many cases anxiety, around the value of sleep. Plenty have developed a reliance on sleeping pills.

A 2016 study on sleep medication and athletic performance stated: “Olympic champions have openly been placed into drug rehabilitation due to dependence on sleep medication.”

In 2012, Australian multiple Olympic champion swimmer Grant Hackett disclosed that he overused sleeping pill Stilnox late in his career. By the time of the 2016 Rio Olympics, in a move strongly opposed by some team members, the Australian Olympic Committee had banned its athletes from using sleep medication.

Pre-Paris Olympics mental health screenings conducted by the US Olympic and Paralympic Committee revealed sleep remained athletes’ “number one concern”.

A spokesman for Hong Kong Sports Institute (HKSI) said: “At HKSI, a comprehensive support system is in place for athletes, which includes resources and advice around optimising sleep.”

The absence of air conditioning from the Paris Olympic Village has left some athletes worried about restless nights. Gregory Koenig, the French coach of Hong Kong fencer Cheung Ka-long, said that if necessary he would use local contacts to install air conditioning in his athlete’s accommodation.

“Previously, everyone knew the obvious, that athletes were more tired after poor sleep, but there was no link between the science and athletic metrics,” West said.

Of 283 elite Australian athletes sampled for a 2015 study, 64 per cent had suffered poor sleep the night before competition over the previous 12 months.

“The poor sleep reported by athletes … was situational rather than a global sleep problem,” said the study.

West views a large part of her role as “creating resilience towards poor sleep”. “Everyone can tolerate a bad night,” she said.

“We create a lot more fear around sleep, than we see sleep as an opportunity.

“There is a logical explanation for athletes struggling to sleep before competition. When we are nervous, we produce more cortisol and adrenaline, the hormones working against sleep.”

Bryony Page, the British trampolinist, said she “probably only slept two hours because of the buzz and excitement and adrenaline”, the night before claiming silver at the Rio Olympics. “I just rested my eyes and accepted that was going to be that,” Page said.

Sleep expert Richard Swinbourne, whose 2015 presentation to local athletes is housed on the HKSI website, describes the body as a “survival machine”. “If you are put under the pump and have to perform, you can,” he said.

At the height of his career, Roger Federer reportedly slept 11 to 12 hours each night. Usain Bolt had eight to 10.

“Sleep is extremely important for me,” Bolt said. “I need to rest and recover for the training I do to be absorbed by my body.”

Trying to consistently manage those unbroken stretches following late-night competition, or amid the hullabaloo around an Olympics or tennis grand slam, is a recipe for stress.

“The question is, when science and reality aren’t meeting, how can we create a bridge?” West said. “Premier League footballers have late kick-offs. They probably have caffeine before the match. Nothing in their system is building up to a good night’s sleep.

“I never want my athletes to strive for optimal. I want them to strive to optimise within their framework.”

Another cause of sleep anxiety, said West, was a blind trust of data. “We need to take some feedback with a grain of salt, and that requires education,” she said.

“Devices provide generic feedback, and don’t always take into account what you are doing … or where you are in your athletics cycle.”

The prevailing pursuit of marginal gains, married with some individuals’ profiles, leaves us well informed about athletes’ sleep habits.

Erling Haaland, the Manchester City striker, tapes his mouth shut to encourage nasal breathing, which is said to speed recovery and reduce daytime fatigue.

“I am not a fan of mouth taping,” West said. “After [Haaland’s revelation], I got a storm of questions from footballers.

“It is not that [mouth taping] is why he sleeps well. If you don’t have the basics in place – hydration, nutrition, movement, exposure to light and schedule management – you get no effect from the cherries on top.”

Recognition of advantages from efficient sleep means we now “accept everything in the 24-hour cycle is defining performance potential”, according to West.

“We need to address the root cause of any components around their physiology that are causing a sleep deficit. Changing mattress isn’t going to be the solution. If they have anxiety, we need to understand where it stems from, and learn to deal with it in the day.

“The most impactful time [to implement sleep behaviours] is during preparation for competition. Athletes will have both good and bad nights [during Olympics] and if they have the strategies to embrace both, sleep is exceptionally powerful.”