Study design
It was conducted in the form of online survey. Questionnaires were distributed through wechat and other social platforms, and respondents completed the questionnaires anonymously through wjx.cn. The respondents completed a five-part questionnaire, including basic information (gender, age, education, height and weight), health status (vaccination status, COVID-19 infection status, basic diseases, sedentary time), exercise status (exercise intensity, exercise frequency, exercise time, cardiopulmonary endurance self-assessment), psychological status and sleep status. It takes about 3-5 minutes to complete the entire survey. In previous studies, the sleep and anxiety scales have been well applied, and their reliability and validity have been fully verified. This study has been approved by the Ethics Committee of Beijing Sport University with the approval number 2023013H.