大学新入生の熱中症発生頻度：体育系学部新入生と一般学部新入生の比較

  Purpose: Guidelines for prevention of exertional heat illness issued by academic societies and the Japan Sports Association have been well structured. Although these guidelines have been widely disseminated, the numbers of adolescents suffering heat illness during sports activities is still a concern. Many freshman enrolled in Sports Science-related Departments (SSD) are presumably high-level athletes who engage in high-intensity and/or long-duration exercise during daily practice, and could thus be categorized as a group at high risk of exertional heat illness (EHI). Conversely, the majority of freshman enrolled in non-Sports Science-related Departments (non-SSD) are presumably low-level athletes who might be engaged in comparatively less high-intensity and/or short-duration exercise during daily practice, and could thus be categorized as a group at low risk of EHI. Although sports activities are known to increase the risk of EHI, no evidence is available to suggest whether high-level sports activities increase the risk of EHI. The purpose of the present study was to clarify the prevalence of EHI in SSD and non-SSD freshman.<br> Methods: Four hundred eighty students from SSD and 447 students from non-SSD participated in a self-assessed survey designed to clarify the prevalence of EHI experienced by individuals during the period from elementary school to high school age. Chi-squared and post-hoc residual analysis, and odds ratio (OR), were used to compare differences between the groups.<br> Results: Completed survey questionnaires were received from 480 SSD students and 447 non-SSD students. The prevalence of heat illness was 31.9% in the SSD group and 16.8% in the non-SSD group [adjusted OR 2.342, 95% confidence interval (CI) 1.712, 3.204]. The number of times individuals had experienced heat illness in the past differed between the SSD and non-SSD groups, but the response ratio was similar. More than 85% of students in both groups who had suffered heat illness in the past had done so during club activities at junior high school and high school. The ratio of students who reported ever suffering from heat illness during sports club activities at junior high school and/or high school (n=860) was 25.6%, whereas 13.4% of students reported that they had never participated in junior high school and/or high school sports club activities during the same period (n=67).<br> Conclusion: The present study revealed that high-level athletes (SSD freshman) had experienced EHI twice as often as non-SSD students. In addition, students who had participated in sports club activities at junior high school and/or high school had suffered EHI twice as often as students who had not participated in sports club activities. Coaches and athletes should take more care to prevent EHI during sports and/or physical activities, and when it occurs, steps should be taken to prevent progression to exertional heat stroke.<br>