ABSTRACT
Soccer is the most popular sport worldwide, with over 265 million participants. Soccer is unique in that the ball can be directed deliberately and purposefully with the head, an act referred to as ‘heading’. In recent years, there has been concern about the association between repetitive subconcussive head impacts associated with heading and chronic traumatic encephalopathy. Heading causes immediate changes in biochemical and electrophysiological markers of traumatic brain injury, and some studies have reported brain structural changes and dysfunction in former soccer players. In 2019, it was reported that the mortality associated with neurodegenerative diseases was about 3.5 times higher among former professional soccer players. Following that, in early 2020, the guidance have been published to limit heading by age in some regions including England and Scotland. In this review, we will expound the immediate and long-term effects of heading associated with chronic traumatic encephalopathy and the measures that should be taken into consideration in the practice of soccer instruction, based on the latest findings.