Amy Burk always wanted to play sports. Her first love was basketball, but she quickly realized that because of her visual impairment, she would not be able to keep up.

And so she turned to goalball, a sport specifically designed for the visually impaired. Eventually, the Charlottetown, P.E.I., native made Team Canada and competed at the 2008 and 2012 Paralympics.

In 2015, she was all set to play at the Parapan Am Games at home in Toronto.

And then, suddenly, her dream was ripped away. Burk, who competed as a B3 — the least impaired category in her sport — was told by a classification panel that she was no longer eligible.

"It was essentially a slap in the face," Burk said. "Like being told that I see too well, even though I know I don't. And then that literally took me out of sport. Like what other sport can I play?

"To have the visual impairment that I have, it's very stable. It's a genetic condition. I was born with it. And so to go my whole life, [and then] at 25 to be told you see too good, it's like, well, my vision has never changed."

Burk was unable to compete in Toronto, and still hasn't had the chance to participate in an international event in Canada. 

After six months of ensuing legal battles backed by the Canadian Paralympic Committee, the now 34-year-old was admitted back into the sport, going on to compete at each of the next two Paralympics. Burk is currently the captain of the Canadian goalball team, which is headed to Paris.

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The larger issue of classification, however, remains a thorny subject within Paralympic circles. At its heart, classification — the act of categorizing impaired athletes — is intended to make Para sport equitable. But athletes will tell you that process is not always fair. Many have similar stories to Burk's, or recount competing against those who seemingly did not fit into their category — a phenomenon termed by some as "class doping."

Put simply, classification is meant to have the same effect as weight classes in boxing or age-group competitions for children. A heavyweight fighting a welterweight, or an 18-year-old racing against a 10-year-old, is inherently unequal.

But classification is much more complex. It is a make-or-break assessment conducted by a trio of volunteers, sometimes requiring an athlete to travel halfway across the world, in which your entire athletic career is at stake. 

"You go through the whole in-the-room assessment and then you sit for the longest 10 minutes of your life as they deliberate on which class they think you should fall into," said Canadian Mel Pemble, who competed at Pyeongchang 2018 as a Para skier but is now headed to Paris in cycling.

In the right category, you could be a medal contender. But get placed into a less impaired class and your competitive chances could go out the window.

It's part of the reason Pemble, 24, switched sports in the first place.

"I think maybe as the years went on, there was a question whether I was in the right class and whether I should be in another one," she said. "There were athletes in my class that could use two poles and I could only use one."

Classification, which varies by sport, is typically denoted by a letter followed by a number. The letter stands for the category of impairment — in swimming, you could be S (freestyle, backstroke, butterfly), SB (breaststroke) or SM (individual medley), while cycling categories include H (hand cycle), T (tricycle), C (bicycle) and B (tandem bike).

The ensuing number represents severity, with lower numbers usually indicating greater impairment.

Canada's Nate Riech holds the world record in the T38 1,500 metres. In his case, the T stands for track (field event classifications begin with F), while numbers 35 through 38 are reserved for athletes with coordination impairments. As a T38, he is in the least impaired category.

Boccia player Alison Levine, who's also headed to Paris, is classified as BC4, the least impaired of four boccia categories and reserved for athletes with non-cerebral impairments that also impact their coordination.

"Classification is — excuse the language — classification is hell. It is incredibly difficult," Levine said. "You're subjected to physical manipulations that are, first of all, dangerous for your body and can cause harm and injury, and then you're scrutinized and watched.

"I always get the feeling that you're being treated as if they think automatically everyone's trying to fake their disability or get into a lower class. … Instead of, this is what this person has, let's see their capabilities."

Levine, who has a degenerative neuromuscular disorder, described her experience as consisting of more than 45 minutes of bench testing — a physical assessment meant to measure impairment level, in which athletes are asked to perform certain movements to evaluate muscle function. She was then observed on the boccia court.

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And after all that, Levine said she was told that she could not be confirmed as BC4, and that she would have to reclassify ahead of every competition, because she was unable to show the genetic mark of her disability — one that had not yet been discovered.

Like Burk, Levine fought the ruling with the support of the CPC and eventually had her classification confirmed, successfully avoiding having to constantly repeat the process.

"It's just so anti-athlete centred and it's horrific really. And yet still there's so much discrepancy between zones that people that are classed out in some zones and then are classed in in others. It's mind-blowing," she said.

Without a central international classification centre, classifiers are trained throughout the world and perform their duties free of pay.

Meanwhile, due to required certifications, the classifier pool is shallow.

"Overall in Canada it's been pretty smooth," said CPC chief sport officer Catherine Gosselin-Despres. "I would say that in general, we would need more classifiers in Canada. It's just a volunteer role. It's hard to recruit people. It comes from a specific background. I think if we had more that would make everyone's life easier because there could be more opportunity domestically, and even having more international classifiers would be really great."

Mike Edey, the pathways systems and classification manager for Swimming Canada, oversees domestic classifications, which help burgeoning Canadian Para athletes choose the right development pipeline.

He also volunteers for World Para Swimming as an international classifier and has been on the other side of the process as an athlete representative.

Edey said the most common complaint he's heard from athletes is that classification can be overly intrusive — but he also pointed out that everyone learns to live with their strengths and weaknesses and develops tactics to overcome the latter.

Classifiers, though, must plainly see an athlete's impairment.

"They have to break through that shell, that mask, those coping strategies, those skills that you've carefully honed and developed and been supported in in order to be your best you," he said. "And now they need to measure what you can't do, who you aren't and what you don't have. That is a really hard position to be in."

Like Gosselin-Despres, Edey cited the need for more classifiers worldwide. But he said the biggest flaw in the current system is the lack of access to the potential talent pool.

A larger sample size of Para athlete would provide more information on which categories athletes are best suited for and add more context to the competitions themselves.

There are people who are trying to misrepresent their disability in order to be in a lower category, which is our form of doping. And it's worse in the sense that there are no consequences that come with it.- Canadian Para swimmer Aurelie Rivard

"If you have a statistical outlier, like a Michael Phelps, you can see how much of an outlier they are because they compete against eight billion human beings on the planet. But if you have a very significant activity limitation for sport, and you have a sport class that maybe sits in like the S1, 2 or 3 range, there may be thousands of eligible people in the world," Edey explained. 

"And when you stand atop the podium at a world championships or Paralympic Games, you were the best in the world who was eligible for your sport class, but it's a smaller population. So how do you know when that person is actually an outlier?"

Asked about classification, Canadian Para track cyclist Nathan Clement takes a deep breath: "Oh boy, I hope you're ready for this."

Clement competed at the 2016 Paralympics in swimming before discovering cycling during the pandemic. Now, he's headed to Paris as one of many medal threats for Canada in the sport.

He said he attempts to treat the classification process with the appropriate "dignity," while acknowledging that you also want classifiers to see what you're like before, during and after a race — something that may not be totally possible in one evaluation.

Clement compared classification to essay writing in school.

"Depending on what teacher you have, it might be marked in a different way, or how you put together your paragraphs or put together your sentences might be evaluated differently. So it's always changing," he said.

Confusing matters even more is the issue of class-doping.

Decorated Canadian swimmer Aurèlie Rivard, who is missing part of her hand, said the process itself was fairly straightforward in her case. She also acknowledged the impossibility of having a "100 per cent fair" system.

"There are, though, people who are trying to misrepresent their disability in order to be in a lower category, which is our form of doping. And it's worse in the sense that there are no consequences that come with it," she said.

"If you get caught for doping, if you have a positive test, you are banned, your records fall, your medals don't count, you're suspended, it's public. If you get caught in the wrong category, you are put back in the right one. And that's it. And your records hold."

In 2020, an Indian discus thrower was suspended for two years for intentionally misrepresenting his disability.

Former International Paralympic Committee head Xavier Gonzalez told an Australian news outlet last year that impairment exaggeration to improve classification does indeed happen.

"I cannot say that this doesn't exist. It exists," he said.

Edey said one of the hardest things about international classification is the gravity of the panel's decision.

"There's a selection bias towards those who are going to be very competitive in their sport class because you already have a leg up, which means you're always in danger of moving to a sport class where you'll be less competitive. And this could be forever," he said.

Meanwhile, athletes will try to gain every competitive advantage they can. Like drug doping, it is up to those in charge to draw the lines and identify those who cross them.

Multiple athletes, including Rivard, admitted that they sometimes size up their opponents and wonder if they truly belong in the same class.

But once the competition begins, the athlete cliché of controlling the controllables clicks in.

"I see my girlfriends who complain. They only talk about how this girl has this, this girl has that, and it's draining for them. It's the wrong thing to focus on," Rivard said. "And that's one of the things that I learned too over the years is how stressful it is to worry about the other people. I can't be in your head. I can't do anything for you. So I try to just always bring it back to me."

In team sports, classification works somewhat differently. Wheelchair rugby players are categorized by points — from 0.5 (most impaired) to 3.5 (least impaired) — and teams can only field a maximum of eight total points on the court at once. Wheelchair basketball classifies players from 1 to 4.5, with a 14-point maximum on the court.

Sitting volleyball has just two categories — SV1 (most impaired) and SV2 (least impaired). Teams are only permitted two SV2s on their roster, and only one can play at a time.

In a way, the stakes are even higher during sitting volleyball players' classifications, since being labelled an SV2 could push you out of the sport entirely if there's no room on the national team.

"The fate of your athletic career kind of literally is in the hands of somebody who's assessing your level of disability," said Heidi Peters, who's competed on Canada's women's sitting volleyball team since 2013.

When you get a [classification] result that's significantly different from what you're expecting, it can be pretty off-putting and disconcerting.- Canadian Para rugby player Travis Murao

Travis Murao, a two-point player for Canada's wheelchair rugby team, said his sport's classification system is outdated, since it wasn't originally designed for athletes like him with spinal-cord injuries.

"When you get a result that's significantly different from what you're expecting, it can be pretty off-putting and disconcerting," he said. "And equally so when you see a player from another country receiving an incorrect classification. It can be pretty startling. So I think that's one of the major issues that we'll never get perfect."

Like in individual sports, class-doping in team sports manifests itself by athletes trying to exaggerate their impairment to receive a lower class.

But in the 4.5-point range for wheelchair basketball players, athletes are at the risk of being classed entirely out of their sport — something that recently happened to Canadians Sandrine Bérubé and Danielle Duplessis.

Canadian captain Cindy Ouellet said it shouldn't matter because "we're all still playing in chairs."

"You don't get an advantage, like maybe in swimming or track. But everybody plays in a chair. So either you have your full function of your knee or half function, it won't matter, you're still a 4.5," she said.

Yet classifiers like Edey would say they are making the most equitable decisions possible, even if they may not feel fair to athletes.

"We try as a sport to give a classification panel and the athletes and those knowledgeable within the sport the largest number of qualitative tools possible in order to — I wouldn't say justify sport class — but in order to illustrate the process by which sport class was assigned," Edey said. 

"But at the end of it, there's still a panel who has to make a qualitative judgment."

Still, asked in black-and-white terms whether the classification system works, Edey said it does.

After Paris, a new IPC code will come into effect to regulate classification. Gosselin-Despres said the CPC was "consulted quite heavily" in drafting the new document and said it is an improvement on the current version, noting specifically the appeal process and new "athlete-focused language."

The Quebec City native added that the CPC's job in the process is to back its athletes.

"Sometimes it's just what you need to do. The athlete may be in a different class, but you'vre got to do it so that they know you're in their corner and this is how they're going to be feeling good about the situation," she said.

As for the athletes, they must learn to live with the imperfections of the system.

"In sport you have to push yourself to your limits," Clement said. "And it's not always gonna be going your way and the results will never be 100 per cent perfect, but you have to push yourself and put yourself in the best position to be the best performer that you can be despite everything that's going on around you."