As Canada's 162 Paralympians march into Rio's Maracana Stadium Wednesday for the opening ceremony, they know interest in the competition and their events will inspire millions of Canadians.

Much harder to know, is how long that inspiration will last and what impact it will have shifting broader perceptions of those with disabilities.

Twenty-eight years after the Paralympics were wedded to the Olympic schedule by holding the competition immediately afterwards, athletes say interest in sports for the disabled is surging.

"Of course it is, " said David Eng, Canada's official Paralympic flag bearer in Rio.

The three-time Paralympic medalist is co-captain of the wheelchair basketball squad and has represented Canada four times, the first in 2004 in Greece.

"In 2004 it (the Paralympics) wasn't as popular. But in China, the inclusiveness changed. And London was a whole other level," said Eng.

​London breakout

The 500 hours of Paralympic events broadcast at the London 2012 games was a record.

Two years earlier at the winter games in Sochi more than five million Canadians watched the winter Paralympic games the first weekend alone.

Canada's wheelchair rugby program has been among the beneficiaries of the added public interest.

Zak Madell, 22, is one of Canada's most talented wheelchair rugby athletes and part of a team that won silver in London. (Chris Corday/CBC)

"It's amazing to see the growth of the sport since I started," said Canadian wheelchair rugby star Trevor Hirschfield, who's making his fourth Paralympic appearance.

"The top five teams in the world are now neck and neck – it's amazing to see the growth in that," he said. "It used to be just a couple of teams here and there."

Positive emotions

The International Paralympic Committee says its surveys suggests the Paralympics generate much more positive emotional reaction than the summer and winter Olympic events, and almost four times the positive feelings as top professional sports such as soccer.

The focus of Canada's Paralympic marketing has also matured.

It has shifted from trying to inspire people with compelling stories of competitors overcoming adversity to emphasizing the athleticism of the games.

The Canadian Paralympic Committee's new Para-Tough campaign features videos of 14 Paralympians working out. It then challenges viewers to try to keep up.

Legacies hard to measure

The International Paralympic Committee also sees the games as a vehicle to change attitudes about disability and to promote inclusiveness in host countries and around the globe.

That part of the Paralympic experience is much harder to measure, say researchers.

University of Western Ontario professor Laura Misener is in Rio as part of the university's Olympic Studies program to examine the question.

"To be honest, we know very little about the legacies a Paralympic games can offer," Misener told CBC News outside Rio's International Broadcast centre facility.

Wheelchair rugby is popular with spectators because it's extremely physical. Players often alter their wheelchairs with tape to help them on during impacts. (Chris Corday/CBC)

She said there's evidence the London games produced "...some shift in terms of greater positive attitude to those with disabilities," particularly in how the media portrayed Paralympic sport and disability in general.

But she cautions it's difficult to know whether the goodwill translated into more accessible infrastructure or other helpful change.

Volunteers gained insight

Laura Misener is a professor of kinesiology at Western University in London, Ont. She's in Rio to study the legacies left by the Paralympic games on host communities. (Chris Corday/CBC) Misener says volunteers who worked directly with Paralympic athletes appear to have gained far more insight than spectators who simply watched the events without interacting with the athletes.

"Volunteers have gone through specific training, they've worked with the athletes, so they are likely to see more change in attitudes," said Misener.

Rio's games have been plagued by money shortages, resulting in fewer volunteers and reduced services such as transportation shuttles.

Misener says it's inevitable those problems will impact the Paralympic legacy the games leave behind for Brazil.