USA Today reported the results of a study that suggests freq…
USA Today reported the results of a study that suggests frequently heading the ball in soccer lowers players’ IQs. A psychologist tested 60 male soccer players ages 14 to 29 who played soccer up to five times per week. Players who averaged 10 or more headers per game had an average IQ of 103, whereas players who headed the ball one or fewer times per game had an average IQ of 112. The experimental units in this study are: