After a fortnight of Olympic excitement, the superhumans have taken the stage: the Rio 2016 Paralympic Games are well underway. The previous edition in London 2012 was a phenomenal success, with record numbers of ticket sales, broadcasters and TV viewers.

Apart from the unprecedented magnitude of the event, the London Paralympics were distinguished by another special feature: after a 12-year-long absence, sports for people with intellectual impairments were once again included in the program. As a result, 120 such athletes went on to compete in track and field, swimming and table tennis events – and many will do so again this year.

As explained by the International Association of Sport for para-athletes with an intellectual disability (INAS), people with an intellectual disability find it harder than others to learn, understand and communicate. Many will find it hard to join a sports club, to enjoy organised sport or to find a coach who will understand their needs.

All too often, sports organisations are simply not accessible, and do not encourage people with an intellectual disability to get involved. Yet with the right support and coaching, an intellectual disability should not be a barrier to enjoying sport.

However, when it comes to competing in events such as the Paralympics, it can be very difficult to assess how intellectual impairments affect sports performance – and this is crucial to ensuring a level playing field.

Fair play

For physical and visual impairments, the International Paralympic Committee (IPC) is continually developing a largely evidence-based classification procedure to sort athletes into different categories for competition. Expert classifiers take responsibility for testing the athletes, and grouping them according to the degree of limitation imposed by their impairment.

For example, when an athlete has only one arm, this may have a large impact on their performance if they are a swimmer, but only a moderate impact if they are a runner. The expert assessors will measure the extent of this impact, and classify the athlete accordingly.

But classifying athletes with an intellectual impairment is much more complicated – not least because this kind of disability can be difficult to verify. This has caused major issues in the past: following the Sydney 2000 Paralympic Games, the victorious Spanish basketball team were later stripped of their medals, when a whistle-blower revealed that only two of the 12 athletes were actually intellectually impaired.

This led to a ban on events for intellectually impaired athletes, until clearer classification procedures were introduced. Now, all competitors must meet the World Health Organisation’s (WHO) definition of intellectual disability: an IQ below 75, which results in impaired social functioning and begins before the age of 18 with a lasting effect on development.

In order to classify athletes in appropriate categories, they are subject to several generic tests assessing intellectual capacity, as well as sport-specific tests to determine how their impairment affects their performance. Science is currently helping to develop these tests, so that athletes can be classified with even greater accuracy, which is vital to ensure a level playing field.

Pace yourself

Take table tennis, for example. So far, research has shown that optimal performance in table tennis is mostly associated with technical proficiency, which includes factors such as accuracy, upper limb speed, reaction time and spatial visualisation.

Studies have also found that athletes with an intellectual impairment are slower and less accurate when returning the ball, and have more trouble with spatial visualisation. As such, the athletes' impairment clearly affects their sporting performance. So developing tests which assess the extent of these impacts could be useful when classifying them for competition.

Currently, our team of experts from the University of Essex and the University of Leuven, are looking into the challenges of 1,500 metre running for athletes with an intellectual impairment.

To give their best performance, athletes must set and adjust their pace, self-regulate the intensity of their exercise and decide how and when to invest their energy. For instance, a runner might hold back at the beginning of a race, in order to conserve energy and sprint to victory at the end.

But data collected in the lab, as well as during organised races, suggest that athletes with an intellectual impairment have more trouble with pacing their race. Instead of keeping a steady pace when instructed to run slower than full speed for 400m, intellectually impaired athletes tend to accelerate towards the finish line.

The ability to pace yourself is a crucial aspect of performance, especially for longer distance races such as the 1,500 metres. So an assessment of this ability could be another positive addition to the Paralympic classification procedures.

Further studies are needed to discover how and to what extent pacing is affected by intellectual impairments in different sports – as well as if adequate pacing is something that can be learned. These findings will also hold interest for other sporting disciplines, such as swimming and potentially cycling. Pacing is also a crucial variable in events such as Nordic skiing, which looks set to be a part of the proposed 2018 Winter Paralympic Games. So similar tests could help to classify athletes competing in this event, too.

Building a greater understanding of how intellectual impairments limit athletic performance through research will help to put in place proper tests and procedures, to ensure a fair competition for all athletes. This, in turn, could open the door to other Paralympic events in the future, and welcome even more people with intellectual impairments into the wonderful world of sports.

Florentina Hettinga, Senior Lecturer Sport Science, School of Biological Sciences, University of Essex

This article was originally published on The Conversation. Read the original article.