Exercise Helps Prevents Alzheimer's
Regular physical exercise is one of the best way to help reduce risk of Alzheimer's Disease. Exercise decreases inflammation and reduces blood sugar levels. It increase blood flow to the brain supplying it with oxygen and nutrients to help support the neurons. And it increase brain-derived neurotropic factor (BDNF), which is akin to a growth factor for the brain.
The role of exercise in reducing Alzheimer's risk has been mentioned in numerous books, articles, and other sources. Here I will just mention some of them.
What kind of exercise? Aerobic exercise in particular.
Dr. Mark Hyman talked about health where says ...
"Exercising is one of the best things you can do to actually prevent Alzheimer's" [22:20 in video]
Exercise increases BDNF (brain-derived neurotrophic factor) in the hippocampus of the brain. This was seen in mouse experiement. Another study showed that exercise increased the volume of certain areas of the brain.
Exercise improves brain health in general. Because what is good for the heart is good for the brain. What keeps your arteries clear and flexible will have a positive benefit on your brain health.
Exercise helps decrease obesity and inflammation. Obesity and inflammation has been associated with increased risk of cognitive decline. Type 2 diabetes is often associated with obesity especially with abdominal fat. Type 2 diabetes characterized by high blood sugar due to insulin resistance. It has been shown that diabetes increases risk of Alzheimer's by many folds. Exercise including resistance training will help reduce blood sugar levels and increase insulin sensitivity.
Physical exercise decrease stress and improve mood, which can improve clarity of thinking.
Even simple exercise like walking is enough to have an effect. A study showed that elderly women who walked more blocks had less cognitive decline. It is best to start exercising earlier in age. However, it is never too late to start. Older adults who start exercising is still better than not exercising at all.
Exercise helps prevent Dementia
Time.com reports of studies that found both aerobic and resistance training exercises showed improvements in several aspects of cognitive functioning and improved memory.
Article on memorylossonline.com says ...
"Evidence is mounting that physical activity -- specifically aerobic exercise -- improves memory and various other brain functions and may lower the risk of dementia."
UCTelevision has a YouTube video "Preventing Dementia: Facts and Fiction" where Brianne Bettcher talked about exercise and how it can stave off Alzheimer's.
Professor of Neuropsychology Joel Kramer gave a talk on the aging brain and how to stall dementia. He says the evidence of exercise is pretty overwhelming. The bottom line is that a high level of activity is associated with 38% decrease risk of cognitive decline. Those who have higher levels of exercise have higher brain volumes including greater volume of white matter and hippocampus. They also have higher cerebral blood flows.
He mentioned that there was a one year study with an aerobic group and an stretching group. They found that the aerobic group had higher hippocampus volume and greater amount of BDNF. There are also mice studies in which mice in the enriched environments with a running wheel has less brain decline.
Why does exercise help? It decreases inflammation which is a factor in brain decline. And it helps you lose weight and improve cardiovascular function.
What's Good for Heart is Good for Brain Health
This is because your brain is filled with tiny arteries and capillaries in order to bring oxygen to your brain cells (of which there are 100 billion of them and trillions more of the brain supportive cells known as glial cells). Exercise improve blood flow and circulation to the brain.
Although your brain is only 2% of the body mass, it consumes on average 20% of the bodies oxygen. Even at rest, it consumes 10% of the body's oxygen. In heavy mental activity, it can use up to half the body's oxygen. So keep those arteries clear; they are the highways that bring oxygen to your brain cells.
Book: "Spark: the revolutionary new science of exercise and the brain"
The book Spark: The Revolutionary Science of Exercise and the Brain provides scientific explanations of how exercise affects the brain.
Author John Ratey explains ...
"The mental and physical disease we face in old age are tied together through the cardiovascular system and metabolic system. A failure of these underlying connections explains why people who are obese are twice as likely to suffer from dementia, and why those with heart disease are at far greater risk of developing Alzheimer's" [page 220]
So in a sense, in order to prevent Alzheimer's, we have to prevent cardiovascular disease and diabetes which is a metabolic disorder. Exercise is a preventive treatment for both these cases.
Exercise: Number One Brain Rule
John Medina wrote a book call Brain Rules: 12 Principles for Surviving and Thriving at Work, Home, and School.
What is his number one rule? That's right. Exercise.
"A lifetime of exercise can result in a sometimes astonishing elevation in cognitive performance, compared with those who are sedentary. Exercise out perform couch potatoes in tests that measure long-term memory, reasoning, attention, problem-solving, and even so-called fluid-intelligence tests." [page 14 of Brain Rules]
Exercise builds new brain cells
Barbara Strauch writes ...
"At this point, the most promising answer is exercise. In one rigorous study after another, exercise has emerged as the closest thing we have to a magic wand for the brain, the best builder of branches, baby neurons, and, along with education, perhaps, the mental padding of cognitive reserve." [p126 of The Secret Life of the Grown-up Brain]
She also writes about how Columbia neuroscientists Scott Small watch new brain cells developed as mice where subjected to exercise. Birth of new brain cells is called neurogenesis. And this process is enhanced with exercise.
Exercise Support Glial
We have 100 billion brain cells. But we also have trillions more glial cells in our brain. These are supports cells to our neurons.
Article by the DANA Foundation says that ...
"Exercise also seems to benefit glial cells, the nonneuronal brain cells that support synaptic transmission and ensheathe neural fibers with myelin, a fatty substance that speeds nerve signaling. Each of these effects may be driven in part by increased blood flow to the brain, a well-documented benefit of physical activity."