Teens who are in better cardiovascular shape perform better on cognitive tests. More muscle mass does not help. The researchers controlled for genetics by including twins in their analysis.
Pedersen, lead author Maria Åberg of the University of Gothenburg and the research team looked at data for all 1.2 million Swedish men born between 1950 and 1976 who enlisted for mandatory military service at the age of 18.
In every measure of cognitive functioning they analyzed – from verbal ability to logical performance to geometric perception to mechanical skills – average test scores increased according to aerobic fitness.
However, scores on intelligence tests did not increase along with muscle strength, the researchers found.
"Positive associations with intelligence scores were restricted to cardiovascular fitness, not muscular strength," Pedersen explained, "supporting the notion that aerobic exercise improved cognition through the circulatory system influencing brain plasticity."
The fact that muscle strength doesn't boost brain performance suggests better oxygen and nutrient supply to the brain is key.
"Direct causality cannot be established. However, the fact that we demonstrated associations between cognition and cardiovascular fitness but not muscle strength . . . and the longitudinal prediction by cardiovascular fitness on subsequent academic achievement, speak in favor of a cardiovascular effect on brain function," Pedersen said.
The results from twins increases the likelihood that the causal relationship runs from cardiovascular health to brain performance.
Even among identical twin pairs, the link between cardiovascular health and intelligence remained strong, according to the study. Thus, the results are not a reflection of genetic influences on cardiovascular health and intelligence. Rather, the twin results give further support to the likelihood that there is indeed a causal relationship, Pedersen explained.
So how is your cardiovascular fitness? Ever run or swim or at least walk rapidly long distances?
|Share |||Randall Parker, 2009 December 17 09:46 PM Brain Performance|