Evidence map›Paper›PMID 41181315›Full record

ArticleBMJ open sport & exercise medicine2025

COVID-19 infection and return-to-play outcomes of elite athletes in Japan: a retrospective descriptive study.

Kazutaka Fukushima, Kazuyuki Kamahara, Anna Tomori, Yoshio Nakata

Abstract read
In one paragraph

Article in BMJ open sport & exercise medicine, 2025. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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1 · What the graph read from it

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2 · The registry

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3 · Its place in the literature

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4 · The record

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5 · Who and what money

Authors and funding

4 authors.

Kazutaka FukushimaDepartment of Sport Medicine, Japan Institute of Sports Sciences, Japan High Performance Sport Center, Tokyo, Japan.ORCID https://orcid.org/0009-0001-2004-628X
Kazuyuki KamaharaDepartment of Sport Medicine, Japan Institute of Sports Sciences, Japan High Performance Sport Center, Tokyo, Japan.
Anna TomoriDepartment of Sport Medicine, Japan Institute of Sports Sciences, Japan High Performance Sport Center, Tokyo, Japan.
Yoshio NakataInstitute of Health and Sport Sciences, University of Tsukuba, Ibaraki, Japan.ORCID https://orcid.org/0000-0002-0888-4440

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Objectives: To describe the characteristics of COVID-19 among elite Japanese athletes and their return-to-play (RTP) time. Methods: We retrospectively reviewed clinical records at the Japan Institute of Sports Sciences between June 2022 and May 2023. Elite athletes who underwent periodic health examinations were examined by a physician to confirm COVID-19 history, symptoms and the RTP time. Results: Of 994 athletes, 456 had a COVID-19 history (mean±SD, 23.3±4.6 years; 56% male). Most infections occurred during the sixth wave (Omicron variant), followed by the seventh and eighth waves, with 88% recorded after the fifth wave. Indoor athletes were more frequently affected than outdoor athletes (306 vs 150, p<0.05). Badminton athletes were the most commonly affected athletes (16%), followed by volleyball (10%) and handball (7%). Among those with a history of COVID-19, 89% reported symptoms, while 11% were asymptomatic. Fever was the most common symptom (80%), followed by sore throat (58%) and cough (44%). The median (IQR) RTP time was 10 (7-14) days. Overall, 472 athletes resumed play within 28 days, while 20 returned after 28 days. RTP delays were more frequent before Omicron (9/59 athletes) than after (11/433 athletes, p<0.05). Conclusion: COVID-19 was more common among indoor sports athletes, primarily during the Omicron wave, with most cases being symptomatic but resolving quickly. These findings likely reflect factors such as close-contact training, immune changes during intensive training and international travel and may help characterise COVID-19 outcomes in elite athletes.

Indexed as

AthleteCOVID-19Elite performanceEpidemiologySports medicine

Identifiers

PMID41181315
PMCPMC12574401

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.