March 11-17, 2019 was Brain Awareness Week, marking the Dana Foundation’s global campaign to increase public awareness of the progress and benefits of brain research. In terms of promoting brain health in ourselves and our families — a topic we know our readers have a lot of interest in — one of the most exciting new areas of study in brain science is the effect of exercise on the brain.
We spoke with Judy Cameron, Ph.D., a Professor of Psychiatry and Director of Science Outreach at the University of Pittsburgh, to learn more about recent discoveries and the latest advice on exercise and the brain. The biggest takeaway for seniors and caregivers is this: No form of exercise is too little or too late when it comes to brain health.
Four Ways Exercise Changes the Brain for the Better
1. Exercise Wards Off Anxiety and Depression
Perhaps because exercise stimulates the nervous system and releases a variety of chemicals in the brain, it has been proven to help with anxiety and depression. Says one recent review of the literature published in “Frontiers in Psychiatry,” “the evidence suggests that exercise can improve depressive symptoms and this is observed even in those suffering from major depressive disorder.”
2. Exercise Increases Blood Flow to the Brain
Studies that have been done on both primates and people have shown that exercise increases blood flow to the brain, even in those who are older and have been sedentary. Dr. Judy Cameron explains: “You’re getting more oxygen to your brain, and you’re getting more nutrients. More blood flow to the brain means that cells have more fuel to operate.”
3. Exercise Protects Your Brain Cells
“A very important thing exercise does is it turns on the expression of specific genes,” says Dr. Cameron, “and many of the genes it expresses are neuroprotective: they cause the production and the secretion of proteins that we call neurotrophic factors, meaning they cause brain cells to make substances that protect them from damage.” This is critical, because some chemicals in the environment (such as pesticides) can enter the brain and be toxic or destructive to brain cells. If you’re producing neurotrophic factors, it has a protective effect.
4. Exercise Helps You Produce New Brain Cells
Not only does exercise increase the production of new neurons in the hippocampus, it also increases the production of glial cells, which are the brain’s support network: These cells have protective effects and support the function of neurons, and they are produced throughout the brain. In tests done specifically on older individuals, it seems to be the glial cell production that is affected most strongly with exercise.
How and When Should Seniors Exercise for Maximum Brain Benefit?
We know a lot about what the heart needs for good health: aerobic exercise, like walking fast, jogging, or swimming — anything that gets the heart rate up. Scientists generally assume that if the heart needs aerobic exercise, so does the brain, says Dr. Cameron. Most studies have been focused on aerobic exercise, and what researchers have found is that in older people, exercise results in higher blood flow to the brain, more production of glial cells, and greater neuroprotective effects.
“We have a little bit of data that says the brain is easier to protect than the heart, and you don’t need to get your heart rate up, you just need to move,” says Dr. Cameron. Even naturally occurring activity that doesn’t get your heart rate up — things you do in a normal day like standing or walking down the hall — can be neuroprotective. The effects are somewhat age-dependent: in primate studies, increased production of neurons only seems to happen in younger groups, the equivalent of humans aged 30-40. But the other positive effects are undeniable. Dr. Cameron points out that it’s an incredibly positive message to bring to seniors: the fact that even small increases in exercise protect the brain.
“That’s a message that we really need to get out there, she says. “You don’t need to exercise and sweat. If you just move more, it will be good for your brain. It’s not such a high hurdle.”
Even if you have minor mobility problems such as stiffness, Dr. Cameron stresses, that’s no obstacle. “You don’t need to formally exercise. Park your car further away from the store, and walk a little bit more. Go up and down every aisle of the grocery store instead of just skipping to the ones you need.
“That’s something that’s attainable by everybody.”
Exercise and Dementia Prevention
These aren’t the only ways exercise benefits senior brain health. There’s also increasing evidence that exercise can help prevent or improve dementia symptoms, and affect alertness, attentiveness, and memory. A study by the Center for BrainHealth at the University of Texas at Dallas found that “engaging in a physical exercise regimen helps healthy aging adults improve their memory, brain health and physical fitness.” Both the researchers and Dr. Cameron attribute this to the increased blood flow promoted by exercise.
“Most people who study Alzheimer’s disease strongly believe that the reason exercise delays the onset of dementia is that it increases heart health, and it increases blood flow to the brain,” says Dr. Cameron. “The highest risk factor of getting dementia is poor blood flow to the brain.” On the flip side, the Center for BrainHealth study showed that exercise promoted blood flow to the anterior cingulate, a part of the brain linked to cognition, and to the hippocampus, which is the key brain structure involved in Alzheimer’s disease.
So seniors and caregivers take note: it’s never too late to start exercising, and you could reap a range of mental as well as physical benefits.
Source : Affects of Exercise on Brain