Latimes.com - December 8, 2009
Fit teens could be smarter teens
Exercise provides a terrific brain boost, as a number of studies have shown. But cardiovascular fitness may trump strength training, according to new research.
The study found that having better cardiovascular health as a teenager was linked to not only higher scores on intelligence tests, but more education and a higher income years down the road.
Researchers from Sweden and USC examined data on 1.2 million Swedish men born between 1950 and 1976 who also enlisted for the country's mandatory military service. They looked at the participants' global intelligence scores as well as logical, visuospatial, verbal and technical scores. The greater the cardiovascular fitness, the higher the cognitive scores at age 18. The association between muscle strength and global intelligence, in contrast, was weak.
The study authors also determined that those who showed cardiovascular fitness improvements between age 15 and 18 had higher intelligence scores than those whose fitness levels dropped. The same results were seen on logical, visuospatial, technical and verbal tests as well. Having better cardiovascular fitness at age 18 was associated with higher levels of education and income later in life.
The researchers speculate that those later teen years are critical because the brain is still changing.
"During early adolescence and adulthood, the central nervous system displays considerable plasticity," said Nancy Pedersen, the study's co-author, in a news release. "Yet, the effect of exercise on cognition remains poorly understood."
Pedersen, a research professor of psychology at the USC College of Letters, Arts & Sciences, added that although causality can't be proven, "The results provide scientific support for educational policies to maintain or increase physical education in school curricula. Physical exercise should be an important instrument for public health initiatives to optimize cognitive performance, as well as disease prevention at the society level."
The study appears in the current edition of Proceedings of the National Academy of Sciences Early Edition.