Can physical activity influence cognitive function?
The relationship between PA and cognitive function remains unclear. Regarding physiological effects, one hypothesis is that PA can counter age-related decline in cardiovascular function associated with brain hypoxia and consequent cognitive decline. Dishman suggested that increased oxygenation of the brain may stimulate and protect the central nervous system [15]. Only a handful of studies have systematically investigated the association between PA and cognitive function. Stewart et al. reported that physically active subjects were 50% less likely to present with cognitive impairment (OR = 0.48; 95% CI= 0.23–1.02) [16]. Schuit et al. (2001) also found that adults who exercised at least 30 min/day had higher MMSE scores than older adults who did not (p < 0.05) [17]. This same group showed that carriers of the ε4 allele of the apolipoprotein E (APOE), a genetic risk factor for AD, have a 13.7-fold increase in the risk of cognitive decline (95% CI: 4.2–45.5) if they perform less than one
