 - Increase in brain activity, measured with functional magnetic resonance imaging, during cognitive tasks In each and every subject, variations in cognitive function, as measured with functional tests and imaging, will be correlated with variations in the cardiovascular parameters, so to explore the relationship between changes in brain and cardiovascular fitness. If the study shows any benefit in the intervention arm, another objective will be the development of a non-pharmacological preventivetherapeutic strategy easily applicable to man. 