Assistant Professor MATSUI Takashi, Institute of Health and Sport Sciences

Most modern cognitive activities and work are conducted in cyberspace using the internet. The COVID-19 pandemic has reinforced this trend, resulting in many people spending entire days at home or in the office, glued to computers or smartphones, thereby often feeling isolated. This lifestyle has highlighted issues such as fatigue and loneliness.
Professor MATSUI views competitive gaming, known as esports, as a perfect scientific model and focuses on visualizing cognitive fatigue, which is often difficult to detect, and understanding how social bonds are formed through modern cyber activities. He coined the term esports-do (the esports way) to emphasize a holistic approach to modern humans by esports science, much like the philosophical and physical aspects of Judo (the gentle way) as Japanese martial arts.

Interestingly, Professor MATSUI is a fifth-degree black belt in Judo who won an international tournament as part of the University of Tsukuba's Judo team. His research journey, therefore, began with his love for Judo. During his graduate studies, Professor MATSUI began researching brain fatigue, spurred on by his experiences in Judo matches against larger opponents. He would hold his own until mid-match but ultimately lost due to fatigue. The resulting frustration led him to investigate the nature of fatigue.
Fatigue can be classified as muscle fatigue (peripheral fatigue) and brain fatigue (central fatigue). Muscle fatigue occurs when glycogen, a stored form of sugar, is depleted in the muscles. Recently, it was discovered that the brain also contains glycogen, although its role was initially unclear. Professor MATSUI and his team conducted animal experiments and found that during exercise, brain glycogen is consumed while the lactate levels rise, leading to central fatigue. He notes, "While the initial goal was to overcome exercise-induced fatigue, we discovered that fatigue helps prevent overexertion." This research was eventually expanded to study brain fatigue in esports.

The founder of Kodokan Judo and the former principal of Tokyo Higher Normal School (now the University of Tsukuba), Jigoro Kano, coined the phrase "Seiryoku Zenyo Jita Kyoei" (maximum efficiency with mutual prosperity)." This doctrine embodies the spirit of Judo, highlighting the importance of building personal strength, human connections, and mutual development through Judo practice.
Professor MATSUI is also the Basic Science Team Leader at the Scientific Research Department of the All Japan Judo Federation. His research on fatigue, which can enhance individual performance, aligns with the principle of "Seiryoku Zenyo." Scientific studies also support the concept of "Jita Kyoei" in Judo. In collaboration with the University of Tsukuba's Judo team, saliva samples were collected before, during, and after the practice sessions to measure oxytocin levels. The results showed increased oxytocin secretion during practice. Oxytocin, often called the "love hormone" or the "bonding hormone," is released during childbirth, breastfeeding, and romantic activities. Professor MATSUI states, "We demonstrated that Judo scientifically fosters empathy and human connections, epitomizing 'Jita Kyoei.'"

Professor MATSUI striking an "e" pose with students in the esports lab

These results came to light around 2019, just as esports were being introduced as a cultural program at the Ibaraki National Sports Festival (now JAPAN GAMES). Visiting the esports venue sparked an idea in Professor MATSUI: Could esports also stimulate oxytocin production? He remembered the sense of connection he felt while playing fighting games with older children at an arcade when he was young, likening it to practicing Judo.
To explore this, Professor MATSUI measured the oxytocin levels and heart rates of student players participating in a campus esports tournament. The results showed that face-to-face matches, even with strangers, increased the oxytocin level and the heart rate, similar to Judo. Unfortunately, online matches did not have the same effect. However, showing opponents' faces on the screen partially increased oxytocin levels. When players wore vests that transmitted opponents' heartbeat through vibrations, oxytocin levels reached 90% of the levels seen in face-to-face matches.
These insights into esports' bonding effects have broader applications in modern society. For example, older individuals playing esports at day centers or with their grandchildren can reduce loneliness and enhance their well-being. Professor MATSUI's research also shows that combining light exercise with esports improves cognitive functioning in older adults. Addressing loneliness is a universal challenge in today's society and not only for older adults. Since esports do not require intense physical activity, they are, therefore, inclusive, allowing participation by older adults and individuals with physical disabilities, fostering teamwork and cohesion in organizations.

However, prolonged play in esports, due to minimal physical fatigue, can instead lead to a risk of "cognitive fatigue," impairing brain function even when physical tiredness is not felt. William Shakespeare once said, "The eyes are the window to the soul," guiding Professor MATSUI's research into using the eyes to detect cognitive fatigue. Recent studies have shown that pupil size can indicate brain activity. Research with esports players at the University of Tsukuba and Akihabara gaming communities found that changes in pupil size correlate with cognitive fatigue, making it a reliable indicator of fatigue. Participants did not feel physically tired until two hours into esports. However, cognitive fatigue tests at that point revealed its presence, with pupils shrinking by about 0.1 mm, indicating fatigue before it was noticed physically. These findings have broader applications, such as in detecting fatigue in office workers who spend long hours on their computers.

Esports serve as a scientific model for modern cognitive activities and work,"
says Professor MATSUI

Professor MATSUI envisions a future in which the principles of esports science are socially implemented to promote positive behavioral changes, enhancing both performance and health in the human body and mind. This paves the way for what he calls esports-do.

Article by Science Communicator at the Bureau of Public Relations