{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,9]],"date-time":"2026-06-09T03:59:49Z","timestamp":1780977589492,"version":"3.54.1"},"reference-count":28,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,18]],"date-time":"2021-09-18T00:00:00Z","timestamp":1631923200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Japan Sports Agency","award":["Sports Research Innovation Project (SRIP) grant"],"award-info":[{"award-number":["Sports Research Innovation Project (SRIP) grant"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>The COVID-19 pandemic has negatively impacted sporting activities across the world. However, practical training strategies for athletes to reduce the risk of infection during the pandemic have not been definitively studied. The purpose of this report was to provide an overview of the challenges we encountered during the reboot of high-performance sporting activities of the Japanese national handball team during the 3rd wave of the COVID-19 pandemic in Tokyo, Japan. Twenty-nine Japanese national women\u2019s handball players and 24 staff participated in the study. To initiate the reboot of their first training camp after COVID-19 stay-home social policy, we conducted: web-based health-monitoring, SARS-CoV-2 screening with polymerase chain reaction (PCR) tests, real-time automated quantitative monitoring of social distancing on court using a moving image-based artificial intelligence (AI) algorithm, physical intensity evaluation with wearable heart rate (HR) and acceleration sensors, and a self-reported online questionnaire. The training camp was conducted successfully with no COVID-19 infections. The web-based health monitoring and the frequent PCR testing with short turnaround times contributed remarkably to early detection of athletes\u2019 health problems and to risk screening. During handball, AI-based on-court social-distance monitoring revealed key time-dependent spatial metrics to define player-to-player proximity. This information facilitated appropriate on- and off-game distancing behavior for teammates. Athletes regularly achieved around 80% of maximum HR during training, indicating anticipated improvements in achieving their physical intensities. Self-reported questionnaires related to the COVID management in the training camp revealed a sense of security among the athletes that allowed them to focus singularly on their training. The challenges discussed herein provided us considerable knowledge about creating and managing a safe environment for high-performing athletes in the COVID-19 pandemic via the Japan Sports\u2013Cyber Physical System (JS\u2013CPS) of the Sports Research Innovation Project (SRIP, Japan Sports Agency, Tokyo, Japan). This report is envisioned to provide informed decisions to coaches, trainers, policymakers from the sports federations in creating targeted, infection-free, sporting and training environments.<\/jats:p>","DOI":"10.3390\/ijerph18189865","type":"journal-article","created":{"date-parts":[[2021,9,20]],"date-time":"2021-09-20T07:52:14Z","timestamp":1632124334000},"page":"9865","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Successful Reboot of High-Performance Sporting Activities by Japanese National Women\u2019s Handball Team in Tokyo, 2020 during the COVID-19 Pandemic: An Initiative Using the Japan Sports\u2013Cyber Physical System (JS\u2013CPS) of the Sports Research Innovation Project (SRIP)"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4176-689X","authenticated-orcid":false,"given":"Issei","family":"Ogasawara","sequence":"first","affiliation":[{"name":"Department of Health and Sport Sciences, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shigeto","family":"Hamaguchi","sequence":"additional","affiliation":[{"name":"Department of Infection Control and Prevention, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan"},{"name":"Division of Infection Control and Prevention, Osaka University Hospital, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ryosuke","family":"Hasegawa","sequence":"additional","affiliation":[{"name":"Department of Information Networking, Graduate School of Information Science and Technology, Osaka University, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yukihiro","family":"Akeda","sequence":"additional","affiliation":[{"name":"Department of Infection Control and Prevention, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan"},{"name":"Division of Infection Control and Prevention, Osaka University Hospital, Osaka 5650871, Japan"},{"name":"Japan-Thailand Research Collaboration Centre on Emerging and Re-Emerging Infections, Research Institute for Microbial Diseases, Osaka University, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Naoki","family":"Ota","sequence":"additional","affiliation":[{"name":"Department of Infection Control and Prevention, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3753-4140","authenticated-orcid":false,"given":"Gajanan S.","family":"Revankar","sequence":"additional","affiliation":[{"name":"Department of Health and Sport Sciences, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan"},{"name":"Institute for Transdisciplinary Graduate Degree Programs, Osaka University, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8252-7281","authenticated-orcid":false,"given":"Shoji","family":"Konda","sequence":"additional","affiliation":[{"name":"Department of Health and Sport Sciences, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Takashi","family":"Taguchi","sequence":"additional","affiliation":[{"name":"Japan Handball Association, Tokyo 1600013, Japan"},{"name":"Faculty of Economics and Information, Gifu Shotoku Gakuen University, Gifu 5008288, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Toshiya","family":"Takanouchi","sequence":"additional","affiliation":[{"name":"Japan Handball Association, Tokyo 1600013, Japan"},{"name":"T-function Inc., Tokyo 1560042, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kojiro","family":"Imoto","sequence":"additional","affiliation":[{"name":"Japan Handball Association, Tokyo 1600013, Japan"},{"name":"Department of Orthopedic Surgery, Japanese Red Cross Kumamoto Hospital, Kumamoto 8618520, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5323-0350","authenticated-orcid":false,"given":"Nobukazu","family":"Okimoto","sequence":"additional","affiliation":[{"name":"Japan Handball Association, Tokyo 1600013, Japan"},{"name":"Medical Corporation Okimoto Clinic, Hiroshima 7340304, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katsuhiko","family":"Sakuma","sequence":"additional","affiliation":[{"name":"Japan Handball Association, Tokyo 1600013, Japan"},{"name":"Department of Rehabilitation, Medical Corporation Yamabe-Kai, Kumamoto Seijo Hospital, Kumamoto 8618072, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7563-6191","authenticated-orcid":false,"given":"Akira","family":"Uchiyama","sequence":"additional","affiliation":[{"name":"Japan-Thailand Research Collaboration Centre on Emerging and Re-Emerging Infections, Research Institute for Microbial Diseases, Osaka University, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keita","family":"Yamasaki","sequence":"additional","affiliation":[{"name":"Department of Health and Sport Sciences, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Teruo","family":"Higashino","sequence":"additional","affiliation":[{"name":"Japan-Thailand Research Collaboration Centre on Emerging and Re-Emerging Infections, Research Institute for Microbial Diseases, Osaka University, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazunori","family":"Tomono","sequence":"additional","affiliation":[{"name":"Department of Infection Control and Prevention, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan"},{"name":"Division of Infection Control and Prevention, Osaka University Hospital, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ken","family":"Nakata","sequence":"additional","affiliation":[{"name":"Department of Health and Sport Sciences, Graduate School of Medicine, Osaka University, Osaka 5650871, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Hermassi, S., Bouhafs, E., Bragazzi, N., Ichimura, S., Alsharji, K., Hayes, L., and Schwesig, R. 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