Exposure to ice water, despite its growing popularity and documented health benefits, is limited by the risk of distressing physiological reactions. The aim of this study was to evaluate the relationships between individual, environmental factors and acute tympanic temperature changes during cold exposure. A total of 90 individuals either practicing cold water immersion (CWI) or winter swimming (WS) were enrolled in the study. They were divided into 4 subgroups according to the distance swum (200 m or 450 m) and immersion time (5 or 9 min). The tympanic temperature of all participants was measured, and BMI was calculated. This study found significant pre-post exposure changes in temperature °C (p>0.05) in all the subgroups, except for the group immersed for 5 min. In winter swimmers, a significant negative correlation between BMI and tympanic membrane temperature was found p = 0.006) for both females and males. The greatest change in tympanic temperature occurred in participants with 3 years of experience in practicing those activities. A five-minute immersion in water below 1°C did not allow for the observation of a significant body response to ice water. The results indicate that a higher BMI was associated with a smaller decrease in tympanic membrane temperature in the winter swimming subgroup.
Karafová et al. (Wed,) studied this question.