So let me pass on to you a quote from this excellent book that I picked out of Lara’s library pile:
“But what, exactly, do we know about the effect of gym on GPA? Few researchers have tackled the question, although one study from Virgina Tech showed that cutting gym class and allocating more time to math, science and reading did not improve test scores, as so many school administrators assume it will. Because gym class can mean so many things, research in this area has focused on the correlation between physical fitness and academic achievement. The most telling studies come from the California Department of Education (CDE). Over the past five years, the CDE has consistently shown that students with higher fitness scores also have higher test scores.”
The moral? Exercise makes you smart.
The book is called “Spark”, it is written by John J. Ratey.