Being Physically Fit Helps Protect Brain Health Later in Life

Physical activity is beneficial in aging in more ways than most would think.  Research has shown that exercise not only benefits overall biological health, but particularly enhances brain health and cognitive functioning.

It is well known that those who perform physical activities on a regular basis reap numerous benefits.  People who maintain an active lifestyle have shown to have decreased prevalence of many disorders that include cardiovascular disease, stroke, osteoporosis, type 2 diabetes, and a variety of cancers.  These types of people also have shown to live longer.

Although there is substantial research on the effects of acute bouts of physical activity on body functions, not much research has been done exploring the long-term effects of exercise.  This may be due to the difficulty of discriminating between steady state effects and transient effects from exercise.

Multiple mechanisms are involved in regards to how exercise benefits the body’s systems with differential significance across the various measures of aging and disease.  Some key mechanistic pathways include body mass indices (including fat, muscle, and bone changes), improved vascularization and blood flow, improved aerobic capacity, improved immune function, and neural benefits.

Strong evidence shows that physical activity is significantly related to a decrease in age-related neural (brain) atrophy.  In a study that had 55 participants between 55 and 79 years of age with normal intelligence, researchers observed age-related decreases in brain density, particularly in the prefrontal, parietal, and temporal regions.  They also found that physical fitness helped to spare these same brain regions, meaning that high physical fitness is associated with a reduction in age-related brain atrophy and that fit people tend to have greater brain volume.  The brain’s volume determines how well the brain performs on cognitive tasks.  Studies have shown that greater hippocampal volume (associated with memory function) correlates with improved spatial strategies in older adults.

Other studies have also shown that physical fitness correlates with improved neural functioning. One study compared the effects of physical fitness on cognitive tasks, measured using imaging fMRI.  This study had two groups of participants. In one group, the physically fit was compared with the non-fit.  Physical fitness was determines by the participants’ performance on treadmill tests. The participants’ fMRI data on cognitive tasks was then compared.  In the second group, older adult participants were randomly assigned to a fitness regimen or a control stretching program.  The participants’ cognitive performance before and after training were assessed.  The results of the study showed that all groups performed their tasks adequately, but the group who had high fitness participants exhibited greater ability with increasing task complexity. The high fitness groups also showed higher activation of cortical brain regions associated with effective attention control.  They also showed lower activation of cortical brain regions associated with need for adaptation in responses, which is activated when conflicted information is received.  This study ultimately showed that physical fitness is associated with improved cognitive task performance and improved neural functioning (demonstrated by fMRI activation patterns).

It is clear that maintaining physical fitness is important throughout life, but especially in older ages, when the brain becomes more vulnerable to deterioration and functional decline.  Older adults in nursing homes and assisted living facilities must be encouraged by their care providers to engage in appropriate forms of physical activity on a daily basis to maintain brain health and overall quality of life.