Core Viewpoint - The article highlights the increasing health risks associated with high temperatures, particularly focusing on heat stroke and cold-induced heat illness, and emphasizes the importance of preventive measures and timely medical intervention [1][2][5]. Group 1: Heat Stroke - Heat stroke is characterized by a core body temperature exceeding 42°C, leading to significant organ dysfunction and potential death [2]. - The condition arises when the body's temperature regulation fails, causing cellular energy metabolism disruption, particularly affecting vital organs like the heart, liver, and kidneys [2][3]. - Preventive measures include regular hydration of 200-300 milliliters per hour, balanced nutrition, and avoiding outdoor activities during peak heat hours [3][4]. Group 2: Cold-Induced Heat Illness - Cold-induced heat illness occurs when individuals transition from a cold environment to a hot one, causing symptoms like dizziness and nausea due to rapid temperature changes [5][6]. - To prevent this condition, it is advised to gradually adjust to temperature changes, maintain a maximum temperature difference of 5°C between indoor and outdoor environments, and ensure adequate hydration [7][8]. - Symptoms of cold-induced heat illness can be alleviated by loosening clothing, ensuring ventilation, and consuming small amounts of warm water [7][8].

Group 1 - The article discusses the strongest heatwave of the year affecting various regions in China, with temperatures exceeding 40°C in some areas [1][3] - The Central Meteorological Observatory has issued a yellow warning for high temperatures, indicating widespread high temperatures across more than 2 million square kilometers [1][3] - The heatwave is attributed to the influence of the subtropical high-pressure system, which is expected to continue affecting northern regions for the upcoming week [3][4] Group 2 - Experts clarify that the current humid and hot weather in northern China is not accurately described as "returning to southern weather," but rather as "sauna weather" due to its specific characteristics [2][3] - The high humidity and temperature combination can lead to health risks, including heatstroke and cardiovascular issues, necessitating public awareness and preventive measures [4][6] - The phenomenon of "cold heatstroke" is highlighted, where individuals may experience heat-related symptoms due to sudden temperature changes between air-conditioned environments and outdoor heat [5][6][7]