• Vol.5

Sports for Everyone

Embodied environment research to support high-performance athletes

ISAKA Tadao, Ph.D.Professor, College of Sport and Health Science


At the forefront of sports science, Tadao Isaka facilitates athletes' more effective training and performance with much confidence by grasping their physical and mental conditions. A deeper understanding of the human body through the lens of sports science benefits not only athletes but also all people live healthier lives and maintain high quality of life.

Support the athletes' competitive career with cutting-edge sports science

The outstanding performance of athletes, who strive to transcend not only their own physical limits but also those of humanity, leaves a strong impression upon us. However, it is a well-known fact that the abilities and efforts of athletes alone are nowadays insufficient to enable them to compete in the Olympics, Paralympics, and other global competitions, alongside international athletes who are extremely agile and competitive. Cutting-edge studies on sports science support the competitive career of athletes in every aspect of their training and performance, ranging from the design of uniforms, shoes, and auxiliary equipment to training menus and management of their physical and mental conditions.

Tadao Isaka, Professor at the College of Sport and Health Science at Ritsumeikan University, leads the Institute of Advanced Research for Sport and Health Science, a government-industry-academia-citizen partnership Institute established in 2022. With 117 internal and external researchers from multiple disciplines, the Institute aims to establish a "Center of Excellence (CoE) of High-Performance Athlete Extreme Support Studies," in collaboration with the Japan High Performance Sports Center (HPSC) of the Japan Sport Council, the Japan Institute of Sport Sciences (JISS), and other research institutions. The CoE will utilize the Institute's research facilities, which are on par with those of HPSC and JISS in Tokyo, and support athletes through latest research developments in medicine, informatics, engineering, physiology, psychology, nutrition, and other fields, as well as the latest information and communication technology.

Observe and grasp athletes' conditions and performance by multiple biosignals

"We have three main themes for supporting high-performance athletes," explains Isaka. "The first is the athletes' physical condition, including biorhythm, sleep cycle, and menstrual cycle in female athletes." The circadian rhythm, considered to be closely related to sleep cycle, is one of the factors thought to influence athletes' performance. "One of the advantages of determining the circadian rhythm is to know the timing of your peak performance," continues Isaka. "The core body temperature fluctuates in around a daily cycle, reaching its lowest point while sleeping during the night and its highest point approximately 12 hours later. Around this high point, good records are likely to be achieved in various athletic events."

However, conventional polysomnography, which measures and evaluates sleep condition by measuring brain waves, respiration, and other parameters, requires the examiner to either enter the examinee's bedroom or have the examinee sleep on a laboratory bed. This approach was not practical from the standpoint of protecting the privacy of athletes and not interfering with their daily lives. Another measurement method is the wristwatch-type actigraphy, which is minimally invasive and can be performed by athletes themselves. It utilizes body acceleration to measure the examinee's activity and resting status but cannot obtain some necessary data such as electrocardiograms (ECGs). Thus, Isaka and his team needed to develop a monitoring method that would allow athletes to easily measure their own circadian rhythms at home, while also taking into consideration their privacy.

Isaka introduces the new method as: "We have developed a conditioning support system for athletes that combines smart clothing, which when worn can measure ECG and body movement, with a smartphone application and a server application. Tokyo Olympic hopefuls and Paralympic athletes used the system and provided feedback through their managers or coaches every two weeks. When the system detected a significant change in an athlete's sleep status, we asked the manager or coach if there had been any changes in training or other aspects of the athlete's condition." Instead of contacting the athletes directly, the research team asked the managers or coaches to first check the feedback message from the team to the athletes, and then to convey that feedback to them. On the other hand, the athletes were able to contact the staff directly for any problems with the system to enable the managers or coaches to concentrate solely on utilizing the measurement results.

After the completion of the measurements, Isaka and his colleagues interviewed the athletes, and found that they were able to sleep more regularly than before the measurement and could discuss their sleep situation with their managers or coaches when there were changes in the sleep rhythm. Some athletes also commented that knowing their so-called "high-performance time" was helpful in determining their practice schedule for the day. This "high-performance time" determination would also be useful for athletes, especially those who often travel overseas, in adjusting their sleeping hours before the competition day. Isaka is optimistic about this research: "We have received encouraging feedback from a Paralympic athlete that being able to grasp their circadian rhythm made them feel more confident during the competition, resulting in better performance."

The second theme is the visualization of training results. It usually takes some time before the training begins to pay off. However, if we think like an athlete preparing for a competition, we will want to know whether today's training was beneficial or not in the short term. Isaka says that this research is still in its infancy and not much can be publicized, but it is likely that there are some kinds of biomarkers that will allow the immediate visualization of the effects of training on the body and mind of athletes.

Lastly, the third theme is the visualization of performance during competition. The research team captured athletes' motion by combining multiple all-sky cameras capable of taking 360-degree images. By viewing the footage on a head-mounted display, the athletes can review their performance in three dimensions from the perspective of their managers or coaches. This system has been accepted favorably by the athletes because the new perspective enables them to understand the instructions given to them better than that with the conventional two-dimensional view.

Isaka emphasizes that in conducting these studies, it is of utmost importance to respect the autonomy of the athletes and their managers or coaches. He says that it would be difficult to make the most of the collaboration by forming a good relationship and working together with those who do not have a sense of challenge and a desire to use this kind of support to improve their performance. Also, since it is not uncommon for them to have a long-term relationship with the athletes for a year or so, they need to be very careful that the research does not become too much of a burden for them or negatively affect their training or competitions. "Since we are researchers, we tend to think that we know best how to read the data, but it is important not to impose our interpretation on athletes. When they look at the data from their perspective, they may come up with their own understanding and improvement measures that cannot be measured by physical quantities alone," advises Isaka.

Maximize the power of sports through "Embodied Environment Research"

Sports and health science studies by no means benefit only high-performance athletes. The history of sports science studies at Ritsumeikan University is longstanding, dating back to 1996 when the Department of Robotics was established in the College of Science and Engineering. The Department of Robotics was the first department in Japan to bear the name of robotics and aimed to apply and develop robot technology, which was already being used in industry, to other fields and train young researchers for this purpose. The researchers that gathered at that time included developers of sports equipment and orthotics and experts in human body measurement and sensor technology. In 2002, the Research Center for Sports and Healthcare Technology was established under their leadership and later reorganized into the Research Center for Sport and Health Science.

"From the time when sports science studies were still in their infancy, Ritsumeikan University has believed that the power of sports can be a means of mutual understanding that transcends age, gender, disability, ethnicity, nationality, and other borders," explains Isaka. In 2010, the College of Sport and Health Science was established along with the Graduate School of Sport and Health Science. In 2022, the Research Center for Sports and Health Science was reorganized into the Institute of Advanced Research for Sport and Health Science, which is responsible for not only supporting high-performance athletes but also the entire process from basic research to social implementation.

However, sports science studies alone are insufficient for understanding the human body. Isaka and his colleagues are now working to create a new research field called "Embodied Environment Research" that aims to understand the human body at multiple scales, from microscopic to macroscopic perspectives. Isaka says: "Technology is advancing rapidly, but the human body is not evolving as rapidly as technology is. In other words, we now have various new perspectives, ranging from micro ones such as genes to macro ones such as interactions with others, which enable us to understand our bodies in ways that do not fit within the ordinary framework of sports science studies. Furthermore, humans are now active not only in the real world but also in online spaces including the metaverse. And yet, until now, research on human body has mostly been conducted at micro and macro levels separately, and there has been insufficient research beyond these boundaries." Embodied Environment Science aims to improve the health, longevity, and quality of life of all people, in collaboration with researchers from various fields at Ritsumeikan University and elsewhere.

Isaka says that his busy schedule has reduced the amount of time spent on conducting research, but he looks forward to seeing research results from young researchers and listening to their ideas. "I want the Institute to be a place where researchers can take their time and get excited about the topics they are interested in," concludes Isaka.

ISAKA Tadao, Ph.D.

Professor, College of Sport and Health Science
Research Theme

Evaluation of Joint Torque Shown in Daily Motion/Work, Kinetic/Kinematic Analysis of Sports Motion, and Study on Muscle Strength and Power of Human Performance


Sports Science