IOC Olympian Health Cohort: a study protocol for a 15-year, prospective, Olympian health study across Summer and Winter Olympic sports.

Prevention of sports injury and illness and protection of athlete health are key mandates of the IOC. Methodological limitations in Olympic Games surveillance and retired Olympian studies mean there are gaps in the available evidence on Olympian health and the varied challenges occurring at different stages throughout an athlete's career. This (protocol) paper describes the methods for implementation of the IOC Olympian Health Cohort. The study aims to establish a longitudinal cohort of current Olympians and follow them prospectively (around 15 years) throughout their Olympic careers and retirement. The study will use participants who have completed self-report questionnaires. Olympians will be recruited after each Summer and Winter Olympic Games, and all National Olympic Committee (NOC) athletes aged 16 years or older are eligible. The first phase included the Tokyo 2020/2021 and Beijing 2022 Olympians, with the study promoted via IOC platforms, Athlete365 and NOCs. Questionnaires include baseline demographics, sports exposure and history of injuries and illnesses impacting the athlete's ability to continue to train and/or compete for at least 2 weeks. Questions also address retirement from sports, musculoskeletal, mental and general health, and quality of life measures. This protocol describes the methods for the 15-year global IOC Olympian Health Cohort Study, from participant recruitment to the development and distribution of the study questionnaire. This protocol will be updated to report future changes in the study's conduct or questionnaire content. These data will help identify risk factors and inform risk-reduction strategies. The ultimate goal is to protect the health of all athletes during their careers and retirement.