Environmental health during extreme heat: challenges for the practice of safe physical activity in childhood and adolescence.

This essay discusses evidence and evidence-based strategies to ensure the safety, well-being, and continuity of physical activity for children and adolescents during extreme heat. It emphasizes the adaptation of environments, professional training, and equity in public policies. High temperatures and sedentary behaviors are not isolated challenges, and they create a critical scenario for the health of children and adolescents when combined, with impacts ranging from thermal regulation to mental health, motor behavior, and risk of obesity. The increasing frequency of extreme heatwaves imposes additional barriers to the safe practice of physical activity among this population, further exacerbating preexisting inequalities. Intense heat increases the risk of dehydration, heat exhaustion, and cognitive impairments, particularly in children, who show lower heat dissipation efficiency due to specific physiological characteristics. Exposure to high temperatures reduces outdoor physical activity, contributing to the worsening of sedentary behavior and pediatric obesity. In this context, adaptive strategies become urgent. Key measures include rescheduling physical activity to cooler times of the day, promoting and ensuring adequate hydration, creating shaded and green outdoor spaces, and strengthening public policies aimed at mitigating environmental impacts on children's health. Additionally, training education professionals and adapting school infrastructure are essential to ensure safer and health-promoting environments in the face of climate change.