Exercise found to protect and even improve the aging brain

Exercise and healthy eating are great ways to vitalise life.  This month two new studies (1,2) published in the Archives of Neurology add to the evidence which suggests that regular exercise can help prevent the problems that often occur in thinking and memory that can come with age and also may help to turn back the clock on brain aging.

The first study(1) was set up to examine the effects of exercise on cognition (mental function) and other factors associated with Alzheimer’s disease in older adults suffering with mild cognitive impairments. 

Mild cognitive impairment typically means the individual will have some memory difficulties such as forgetting names or forgetting where things have been placed.  Around 10-15% of individuals with this kind of mild cognitive impairment will go on to develop dementia – this is in contrast to about 1-2% of the general population.

The study(1) was small but well designed.  Participants were assigned to either a high-intensity aerobic exercise or stretching group (the control group).  The exercise group were under the supervision of a fitness trainer and exercised at 75% to 85% of heart rate for 45 to 60 minutes, 4 days per week for 6 months.  The exercise was done using a treadmill or an exercise bike. The control group carried out supervised stretching activities according to the same schedule but maintained their heart rate at or below 50%.  At the start of the study and then at 3 months and 6 months blood was collected and cognitive tests were taken. 

The results(1) at 6 months found that there were sex-specific positive effects, in women,  on cognition as well as various blood-results (mainly related to blood sugar and stress hormones).  6 months of intense aerobic exercise was found to improve cognitive abilities of attention and concentration, organization, planning, and multi-tasking.  In the stretching ‘control group’ cognitive function test scores continued to decline.  Women seemed to benefit a little more from the exercise than men – the reason is not entirely known although in women the exercise also seemed to improve the cells sensitivity to the hormone insulin, men did not show the same improvement in insulin sensitivity.

This is a preliminary study into exercise and brain function and it may well be that the brain can benefit from lower intensity aerobic exercise – current research is underway to find out how much exercise is deemed to be ‘enough’ to benefit the brain.

The other study (2) showed that engaging in moderate physical activity such as brisk walking, swimming, or yoga in midlife or later could cut the risk of developing mild thinking problems.  The study involved over 1300 people without dementia who completed a Physical Exercise Questionnaire.  The frequency of physical exercise among 198 individuals with mild cognitive decline was compared to 1126 with normal cognition.  The results showed that, in both men and women, any frequency of moderate exercise performed in midlife or late life was associated with a reduced risk of having mild cognitive impairment.  Specifically moderate exercise in midlife was associated with a 39% reduced likelihood of developing mild cognitive impairment, and moderate exercise in late life was associated with a 32% reduced likelihood of mental decline.

These two studies support the growing body of evidence showing the benefits of a physically active lifestyle on the brain.  In conjunction with good nutrition I believe that there really are tangible ways to keep the brain healthy.  Please read my previous posts relating to brain health.

(1)Baker LD et al.  2010.  Effects of aerobic exercise on mild cognitive impairment: a controlled trial. Arch Neurol.  67(1):71-9.
(2) Geda YE et al.  2010.  Physical exercise, aging, and mild cognitive impairment: a population-based study. Arch Neurol.  67(1):80-6.
Written by Ani Kowal