Developing thermal prediction models for children in outdoor environments

How children experience warm and hot climates differs from adults, yet most models of thermal responses to the environment are based on adults. We modeled the thermal physiological characteristics of 162 healthy children, ages of 7-14 under light, moderate, and vigorous intensity activities and thermal transitions (alternate movement under sunlight and shade). Subsequently, we built an accurate and rapid prediction model for children's thermal sensation based on relationships between their outdoor thermal physiology and thermal sensation. The range and mean absolute change in rate of skin temperatures were greatest at wrist and lower leg in different stages. These two temperatures best reflected the transient change in thermal environment. At three activity levels and five thermal transitions, the wrist and lower leg skin temperatures were significantly correlated with thermal sensation (P < 0.05). Heart rate (HR) was significantly correlated with thermal sensation only during vigorous intensity activities (P < 0.05). A light and moderate intensity activity model (DTS-kid (LM)) (accuracy: 85.9 %) was built based on the wrist skin temperature (T-wrist) and its change rate, and a vigorous intensity activity model (DTS-kid (V)) (accuracy: 83.9 %) was built based on HR, T-wrist and the change rate of T-wrist.