Unfortunately, the short answer is no. Some studies have shown that physical activity is associated with better cognition and reduced risk of dementia. A new study involved 900 subjects. Cardiorespiratory fitness was measured. Patients with the best fitness and lower weight had most benefit on cognition.
Other studies have shown different results. A study of 1600 sedentary persons measured the benefit of moderate physical activity on cognition. The intervention group did not perform better. Perhaps, a broader lifestyle intervention, including but not only exercise, is needed to promote brain health.
See Neurology, 2016, page 408-409.
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