Group 1 - A 26-year-old patient experienced symptoms of dizziness, vomiting, and weakness after transitioning from an air-conditioned environment to high outdoor temperatures, leading to acute cerebral infarction due to brain vascular spasm [1] - Cold heatstroke, a special type of heatstroke, can occur when moving from a cold environment to a hot one, causing symptoms such as dizziness, nausea, and abdominal pain [1] Group 2 - To prevent cold heatstroke, it is recommended to avoid large temperature differences when transitioning between environments, gradually adjusting indoor temperatures before going outside [2] - Staying hydrated is crucial, with a suggested daily water intake of at least 2.5 liters, and it is advised to consume warm water in small amounts rather than large quantities of cold drinks [2] - Individuals who enjoy swimming should be cautious, as pool temperatures are often lower than air-conditioned rooms, and they should allow time to adjust before entering hot environments [2] Group 3 - Consuming cold drinks immediately after moving from a cold to a hot environment can lead to "brain freeze," which may cause symptoms like headache, nausea, and weakness [3] - If "brain freeze" occurs, it is important to stop consuming cold drinks and apply gentle pressure to the head or sip warm water to alleviate symptoms [3] - Persistent headaches accompanied by visual disturbances may indicate abnormal vascular contraction and require immediate medical attention [3]