Keep Moving, for Your Brain’s Sake

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Brain Training for ChiRunners

The following article entitled: For Your Brain's Sake, Keep Moving, by Gretchen Reynolds of the NY Times Well blog was published Oct. 4th, 2017.

Here's my response to her article:

“Because we can never have enough reasons to keep exercising, a new study with mice finds that physical activity not only increases the number of new neurons in the brain, it also subtly changes the shape and workings of these cells in ways that might have implications for memory and even delaying the onset of dementia.

As most of us have heard, our brains are not composed of static, unchanging tissue, Instead, in most animals, including people, the brain is a dynamic, active organ in which new neurons and neural connections are created throughout life, especially in areas of the brain related to memory and thinking.

This process of creating new neurons, called neurogenesis, can be altered by lifestyle, including physical activity. Many past studies have shown that in laboratory rodents, exercise doubles or even triples the number of new cells produced in adult animals' brains compared to the brains of animals that are sedentary.

But, it has not been clear whether the new brain cells in active animals are somehow different from comparable new neurons in inactive animals or if they are just more numerous.

That question has long interested scientists at the Laboratory of Neurosciences at the National Institute on Aging, who have been examining how running alters the brains and behavior of lab animals.

Last year, in an important study published in NeuroImage, the researchers found for the first time that young brain cells in adult mice that spent a month with a running wheel in their cages did seem to be different from those in animals that did not run. For the experiment, the scientists injected a modified rabies vaccine into the animals, where it entered the nervous system and brain. They then tracked and labeled connections between brain cells and learned that compared to the sedentary animals' brain cells, the runners' newborn neurons had more and longer dendrites, the snaky tendrils that help to connect the cells into the neural communications network. They also found that more of these connections led to portions of the brain that are important for spatial memory, which is our internal map of where we have been and how we got there.

This type of memory is often diminished in the early stages of dementia.

But these findings, while intriguing, involved animals that had been running for a month, which is the equivalent of years of physical activity by people. The researchers wondered whether such changes in neurons and connections might actually begin earlier and maybe almost immediately after the animals began to exercise.

So for the new study, which was published last month in Scientific Reports, most of the same researchers gathered a group of adult, male mice. (Males were used to avoid accounting for the effects of the female reproductive cycle.) The animals were injected with a substance that marks newborn neurons. Half were then allowed to run for a week on wheels in their cages, while the others remained in active. Afterward, some were also injected with the modified rabies vaccine to track new synapses and connections between the neurons.

When the scientists then microscopically examined brain tissue, they found that the runners' brains, as expected, teemed with far more new neurons than did the brains of the sedentary animals, even though the runners had been exercising for only a week.

Interestingly, these neurons also looked unique. They were larger and, as in the study of mice that ran for a month, displayed more and longer dendrites than similar neurons in the other animals. In effect, the young neurons in the runners' brains appeared to be more mature after only a week of exercise than brain cells from in active animals.

These young cells were better integrated into the overall brain circuitry, too, with more connections into portions of the brain involved in spatial and other types of memory. Most surprising to the scientists, these cells also proved to be less easily activated by neurochemical messages to fire rapidly, which is usually a hallmark of more mature neurons. They remained calmer and less prone to excitability than new neurons in the inactive animals' brains.

What these differences in cell structure and connection mean for brain function remains uncertain, though, says Henriette van Praag, a principal investigator at the National Institutes of Health and senior author of this and the earlier study. Neither study was designed to look into whether the running mice thought and remembered differently than mice that were sedentary for most of the day.

But the current study “provides more pieces of evidence that brain cells produced under running conditions are not just quantitatively but qualitatively different” than other neurons, she says, “and these differences are evident very soon” after exercise begins.

Perhaps most important, the new brain cells in the runners tended to integrate into and bulk up portions fo the brain that, if damaged by disease, are associated with early memory loss and dementia, she adds.
Of course, this experiment used mice, which are not people. While some past neurological studies with people have hinted that exercise might alter our brain structure in similar way, she says, that possibility is still theoretical.

Still, she says, “I think it is a very good idea for the sake of the brain to be moving and active.” “

So my first question after reading Gretchen's article is, “Okay, I understand that running helps your brain to build better neural connections and helps to counteract memory loss… but what is it about running that causes this?” I'd love to see a study done that measures the increased amount of oxygen-laden blood to the brain once a person, or a mouse, begins to run. When you start to run your heart beats faster (pumping more blood throughout your body), you breathe more often and, if you're nose breathing as we suggest in ChiRunning, you're increasing the transport of oxygen, not only to your muscles, but to your brain. That can't hurt.

I know for myself that when I run I can think more clearly. It's where I mull over possible topics for blogs, or pick apart my latest running “Aha!” moment. I also use my running time to solve Life's problems. Then, when I come back home afterwards, I feel more grounded in my body. And, even though I might think a lot during the run, I somehow come back much less heady and cerebral than when I take off. It's almost predictable.

So, it doesn't surprise me that what I've been sensing might actually be a real phenomenon and that if I can just keep running into my old age, it might not be my brain that goes first. 

The additional thing that goes on when I'm practicing my ChiRunning technique is that I'm exercising my brain by focusing on what's happening in my body minute-by-minute and constantly making adjustments in my form as a response to the demands of the environment I'm running through… whether it's a city with traffic to dodge, or a trail with the terrain changing under my feet every split second. This type of brain exercise falls into the field of neuroplasticity (the brain's ability to reorganize itself by forming new neural connections throughout life) which is triggered by thousands of in-the-moment shifts in my proprioception.

I'm sure that with more in depth brain studies of runners (or running mice) we'll someday find out that running, when done well, can be a panacea for a lot of what life throws at you.

Posted in Lifestyle, Technique

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