For athletes competing at the Winter Olympics in Beijing, arriving at the Games with a clean bill of health is a crucial part of their preparation.

The prospect of testing positive for Covid-19 -- and thus missing out on the chance of competing -- looms over every athlete ahead of Beijing 2022, which gets underway on February 4.

Amid a plethora of Covid-19 countermeasures, athletes must record two negative tests before departing for the Games and are then subject to daily tests upon arrival.

"One positive test is going to do us in at this point," US mogul skier Hannah Soar told CNN Sport.

"It's super stressful, I didn't know that I really struggled with anxiety to be totally honest until the past couple of months."

Soar competes at Deer Valley Resort, Utah, last February.
Staying Covid-free constitutes an important part of an athlete's preparation for the Winter Olympics.
Soar has been training and isolating in Utah for the past month, which involves living in a separate house to her teammates, ordering groceries for delivery and wearing a KN95 mask under her neck warmer while skiing.
"This is definitely the most drastic we've gone with Covid protocols and that's what we have to do," she said.
"It's crazy and it's wild and it's something that I didn't think that I'd be doing going into the Olympics, but it is what it is and we're handling it the best we can."
She added: "I treat everyone like they have Covid. It creates a lot of anxiety in my life, but hopefully, it gets me to China."
'Persistently positive PCR'
At last year's Summer Olympics in Tokyo, 41 athletes tested positive for Covid-19, many of whom subsequently had to withdraw from competing.
As of Wednesday, 42 people inside Beijing's closed loop bubble for the Olympics have tested positive for Covid-19 since January 4 with more than 42,000 tests conducted inside the bubble.
Organizers hope the closed loop system will restrict the spread of Covid-19 during the course of the Games. It will encompass venues, official hotels and the event's own transport service, effectively sealing off those involved in the Games from the rest of the Chinese population.

The strict measures are a reflection of China's zero-Covid policy, although the emergence of more positive cases connected to the Games seems inevitable.
"[China] may have actually done the best job of any country in the world in controlling the spread of Covid," Dr. William Schaffner, professor at Vanderbilt University School of Medicine, told CNN.
He continued: "They have created this remarkable series of very strict restrictions and controls that will have consequences. There is very little room for interpretation.
"I would imagine that this extraordinarily contagious virus can get through some of those controls nevertheless, and there might well be a few cases of transmission."
Fully vaccinated individuals will be able to enter the closed loop without quarantining, while those who aren't vaccinated will need to quarantine for 21 days upon arrival.
Games participants who test positive will not be able to compete or continue their role in the Games, instead being sent to a hospital for treatment if they are symptomatic, or to an isolation facility if they are asymptomatic.

Recording two negative PCR tests 24 hours apart will enable an individual to end their isolation, but there's no guarantee how long that might take.
"There is no doubt that some people recovering from Covid can have a persistently positive PCR test that can go on for weeks and even beyond a couple of months," said Dr. Schaffner.
"That does not mean you have live virus. That test is so sensitive, it is merely picking up remnants of the virus. You are not contagious to anyone else."
Getting to Beijing -- without Covid
Laura Deas, a skeleton racer from Great Britain, will arrive in China having already experienced the closed loop system while attending a test event in Yanqing -- a mountainous district 75 kilometers (about 46.6 miles) northwest of Beijing -- last year.
"Everything that we did -- training, eating and sleeping -- was all within this bubble, but it felt incredibly organized," she told CNN while self-isolating at home in the UK ahead of the Games.
She added: "It's certainly a challenge and it just means that I can't really live a normal life at the moment ... I've jumped all of these hurdles over the past few years to get to this point and I'm just trying really hard to do all the right things now so that I can get to Beijing safely without Covid."
Close to 3,000 athletes will compete in 15 disciplines across 109 events at Beijing 2022; with the Games fast approaching, they will be all be praying that a positive test doesn't derail their chances.
"I know full well that if I get the opportunity to be there, I'm capable of getting a medal," said Soar, "But if I don't get there, then I can't get a medal.
"So definitely the biggest hurdle for me is just making sure that we get on the hill, we get into our bibs, we get into our start gate and I can push out."