REGULAR EXERCISE INCREASES THE SIZE OF OUR BRAIN
The practice of a sport and the daily physical exercise are essential elements of our wellbeing. Beneficial against dementia and cognitive disorders , stress and mortality reduction , good for cardiovascular health or against obesity and overweight , physical exercise (aerobic exercise) can also improve the function of memory and maintain brain health as we get older. This is revealed by a new study published on November 4, 2017 in the scientific journal Neurolmage .
PHYSICAL ACTIVITY REVERSES THE BRAIN AGING PROCESS
Researchers from NICM and the Division of Psychology & Mental Health at the University of Sydney, Australia, and the Division of Psychology and Mental Health at the University of Manchester, UK, examined the effects of aerobic exercise on a region of the brain called the hippocampus. Structure of the mammalian brain, the hippocampus belongs to the limbic system. It is located in the medial temporal lobe below the surface of the cortex, and plays a central role in memory, spatial navigation, and other brain functions.
The increase in hippocampal volume in response to aerobic exercise has been consistently observed in animal models. However, evidence from human studies is equivocal. Researchers undertook a systematic review to identify all controlled trials examining the effect of aerobic exercise on hippocampal volumes in humans, and applied meta-analytic techniques to determine if aerobic exercise resulted in volumetric increases.
Situation of the hippocampus in the human brain
The effects induced by exercise, prevent volumetric decreases that occur over time with our aging. These results provide evidence that aerobic exercise can be helpful in preventing age-related deterioration of the hippocampus and maintaining neuronal health.
THE HEALTH OF OUR BRAINS DECREASES WITH AGE
The average brain decreases by about 5% per decade after the age of 40, and studies in mice and rats have consistently shown that exercise increases the size of the hippocampus, but up to now, evidence in humans has been inconsistent.
The researchers analyzed 14 clinical trials that examined brain scans of 737 people before and after aerobic exercise programs or under controlled conditions. Participants included a mix of healthy adults, people with cognitive impairment such as Alzheimer’s disease, and people with a clinical diagnosis of mental illness or mental disorders, including depression and schizophrenia. . The ages ranged from 24 to 76 years with an average age of 66 years.
The researchers examined the effects of aerobic exercise, including stationary cycling (exercise bike), walking and treadmill running (treadmill jogging). The duration of interventions ranged from 3 to 24 months with a range of 2 to 5 sessions per week. Overall, the results showed that although exercise had no effect on total hippocampal volume, it significantly increased the size of the left hippocampal region in humans.
PHYSICAL EXERCISE IS ONE OF THE FEW PROVEN METHODS TO MAINTAIN BRAIN SIZE AND FUNCTION WELL INTO OLD AGE
This study provides some of the most definitive evidence to date on the benefits of exercise for brain health. When you exercise, you produce a chemical called brain-derived neurotrophic factor (BDNF), which can help prevent age-related decline by reducing brain damage. ” The neurotrophic factors are a family of proteins responsible for the growth and survival of developing neurons and maintenance of mature neurons “.
Finally, these new data show that, rather than actually increasing the size of the hippocampus per se, the main benefits of the brain are due to aerobic exercise that slows the deterioration of brain size, in other words Exercise can be considered as a maintenance program for the brain.
Along with the improvement of regular “healthy” aging, the results have implications for the prevention of neurodegenerative disorders related to aging (Alzheimer’s disease, dementia, …), even if additional research is needed.