A Swedish study involving 1.2 million Swedish men reveals link between a strong cardiovascular system in young adulthood and IQ and intelligence later in life.  Maria Aberg, from Sahlgrenska Academy (Sweden), and colleagues studied 1.2 million Swedish men, born between 1950 and 1976, who were enrolled in military service. Analyzing physical and IQ test data collected when the men enrolled, the team established a correlation between good physical fitness and better results for the IQ test, with the strongest links found for logical thinking and verbal comprehension. Noting that their findings suggest that only fitness – not strength -- plays a role in the results for the IQ test, the researchers urge that: “These data substantiate that physical exercise could be an important instrument for public health initiatives to optimize educational achievements, cognitive performance, as well as disease prevention at the society level.”