Sports and technology go hand in hand, particularly when it comes to innovative materials. At the 2024 Summer Olympics in Paris, some of Japan’s athletes will wear outfits made from a new fabric that absorbs infrared light. This material is similar to stealth aircraft that avoid radars and detectors.

Contrary to what you may think, this isn’t about improving performance or anything like that. It’s about something completely different: stopping peeping Toms.

Nonconsensual photography

Sexualizing female athletes is far from a new thing, but thermal cameras were an unexpected element in this story.

Infrared cameras detect heat emitted by objects — or in this case, bodies. They operate by capturing infrared radiation, which is invisible to the human eye but can be felt as heat. In 2021, at the Tokyo Olympics, athletes complained to the Japanese Olympic Committee after discovering infrared camera “photos of themselves shared on social media with sexually explicit captions,” according to The Japan Times.

Basically, some thermal devices can reveal the lines of a person’s body or their undergarments through the thin layer of sports clothing. Yes, some people are doing that. Yes, it’s as crazy and invasive as it sounds.

For the past few years, athletes and sports company Mizuno have been working on a special type of fabric that can stop this. The idea isn’t just to make it block infrared cameras — that’s very doable already. The idea is to make it block thermal cameras while not hindering the athletes in any way. More layers typically mean more heat, and for athletes competing in a scorching French summer, more heat is a big problem.

In experiments reported by Mizuno, a printed black “C” under a layer of fabric and the new infrared-absorbing fabric becomes almost invisible when viewed with an infrared camera. The uniforms also struck a good balance, protecting from prying eyes while ensuring that athletes remain cool and comfortable.

Mei Kodama, 25, who took part in the 4×100-meter race at the Tokyo Games in 2021, reportedly tested an outfit made from this fabric and found it “more comfortable than [she] thought”.

“Incorporating the newly developed infrared blocking fabric into sportswear can help reduce the number of athletes that fall victim to illicit infrared photography,” the company said in a release.

A long-lasting problem in Japan

Although Japan is one of the safest and most low-crime countries in the world, its problem with sexualizing women is surprisingly pervasive. For instance, groping attacks are one long-lasting problem; non-consensual photography is another.

The problem of non-consensual photography is so widespread that cameras in Japan must make a shutter sound to ensure that people don’t take hidden, invasive photos. It’s not uncommon to see signs on public transit warning against this type of practice.

Sexualizing, nonconsensual photos are also a problem in sports.

Airi Hatakeyama, a former group rhythmic gymnast and current television reporter in Japan, was shocked to constantly hear photos being taken of her, often in suggestive manners, even when she was still a minor. Reiko Shiota, a badminton player, found photos of her breasts and lower body shared widely on social media.

In 2021, a man in Japan was arrested for taking infrared photos of a female volleyball player with an infrared camera and selling the images. Two years later, authorities in Kyoto prosecuted another man for filming the lower bodies of female runners.

A technology band-aid

New clothes won’t solve such a pervasive problem. Several sports (like gymnastics) are already banning photography, and Olympics authorities are trying to implement stricter measures, but given how widespread and powerful smartphones are, it’s not easy.

Incorporating infrared-blocking fabric can make a small difference, but for athletes who have had to face this type of harassment, it’s an important one. The Japan team will feature the fabric for six female teams.

Japan also passed a law making it a criminal offense to explicitly photograph anyone without their consent, punishable by three years’ imprisonment.

Meanwhile, athletes who know firsthand this problem are producing their own solutions. Aiko Sugihara, a Japanese gymnast who was tired of suggestive photos on social media, has started her own company that produces a leotard that reaches the top of the thighs and covers more of the athletes’ bodies.

Female teams are increasingly demanding to wear shorts instead of more revealing clothing. Strikingly, some committees are against this. Recently, Norway’s beach handball team was fined for wearing shorts instead of bikinis. Female athletes’ push for more inclusive and less sexualised uniforms is telling of how big a problem this is. After all, infrared-blocking clothing is a good start, but it can only get you so far.