Below are some articles from a NYT's blog that has all kinds of intriguing stories about the brain and exercise. If you click on 'read more', it takes you to the entire article on the Times blog.
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How Working the Muscles May Boost Brainpower
Archi Trujillo/Getty Images
Muscles
do appear to affect the mind, according to a study of drugs that
simulate the effects of exercise in mice. Mice that had “exercised” did
better on tests of memory and learning and had far more new neurons in
brain areas central to learning and memory than mice that had remained
quiet in their cages.
Upending the cliché of muscleheads, scientists at the Laboratory of Neuroscience at the National Institute on Aging recently set out to examine whether changes in muscles prompted by exercise might subsequently affect and improve the brain’s ability to think.
Lab animals and people generally perform better on tests of cognition after several weeks of exercise training, and studies have shown that over time, running and other types of endurance exercise increase the number of neurons in portions of the brain devoted to memory and learning. But the mechanisms that underlie this process remain fairly mysterious. Do they start within the brain itself? Or do messages arrive from elsewhere in the body to jump-start the process?
Gretchen Reynolds on the science of fitness.
The researchers were especially interested in the possibility that the action starts outside the brain – and specifically in the muscles. “We wondered whether peripheral triggers might be activating the cellular and molecular cascades in the brain that led to improvements in cognition,” says Henriette van Praag, the investigator at the National Institute on Aging who led the study.
Muscles are, of course, greatly influenced by exercise. Muscle cells respond to exercise by pumping out a variety of substances that result in larger, stronger muscles. Some of those compounds might be entering the bloodstream and traveling to the brain, Dr. van Praag says.
The problem is that exercise is such a complicated physiological stimulus that it’s very difficult to isolate which compounds are involved and what their effects might be. So she and her colleagues decided to study “fake” exercise instead, using two specialized drugs that had been tested several years ago by scientists at the Salk Institute in San Diego.
The drugs had been shown to induce the same kinds of changes in sedentary animals’ muscles that exercise would cause, so that even though the mice didn’t exercise, they physiologically responded as if they had.One of the drugs that they used, known as Aicar, increases the muscles’ output of AMPK, an enzyme that affects cellular energy and metabolism.
Regular endurance exercise, like running or cycling, increases the muscles’ production of this enzyme. In the Salk experiments, Aicar enabled untrained mice to run 44 percent farther during treadmill tests than other, sedentary animals that hadn’t received the drug.
The second compound, GW1516, a cholesterol drug, also stimulates biochemical changes in muscle cells like those caused by endurance exercise. But in the Salk studies, it had amplified endurance primarily in animals that also ran, allowing them to run farther than another set of running mice that didn’t get the drug. But it hadn’t done much muscle-wise for animals that remained sedentary.
By using these drugs in unexercised animals under well-controlled conditions, the scientists from the National Institute on Aging sought to determine whether changes in muscles then initiated changes in the brain.
And as it turned out, muscles did affect the mind. After a week of receiving either of the two drugs (and not exercising), the mice performed significantly better on tests of memory and learning than control animals that had simply remained quiet in their cages. The effects were especially pronounced for the animals taking Aicar.
The results, published in the journal Learning and Memory, showed that the drugged animals’ brains also contained far more new neurons in brain areas central to learning and memory than the brains of the control mice, an effect found by microscopic examination.
Because the two drugs “don’t cross the blood-brain barrier much, if at all,” Dr. van Praag says, “we could be fairly confident that the changes we were seeing were related to an exercise-type reaction in the muscles” and not to brain responses to the drugs.
The message of this finding, she continues, is that “improvements in cognition” that follow exercise “would seem to involve changes throughout the body and not just in the brain.”
Although the exact process isn’t clear, Dr. van Praag speculates that some of the AMPK enzyme created during exercise enters the bloodstream and travels to the brain, setting off a series of new reactions there.
The implication, she continues, is that exercise may need to be aerobic if it’s going to substantially affect the brain. “You probably need to increase blood flow, which mostly occurs during endurance training,” she says. Also, in animal studies, AMPK production has been found to increase principally after running. Of course, “it’s very hard for us to study weight lifting in mice,” Dr. van Praag says, so it’s possible that other types of exercise might improve AMPK production and cognition too, she says.
Interestingly, when the scientists continued injecting mice with Aicar for an additional week, the animals’ brains stopped responding. They actually began losing their augmented ability to learn, compared with the control animals, a finding that suggests, Dr. van Praag says, that drugs may be an unsatisfactory — and potentially detrimental — way to emulate the effects of exercise.
Exercise, on the other hand, is generally safe. “And the scientific evidence, including ours,” she says, “is strong and growing that it is very good for the muscles — and for the brain.”
Gretchen Reynolds is the author of “The First 20 Minutes: Surprising Science Reveals How We Can Exercise Better, Train Smarter, Live Longer” (Hudson Street Press, 2012).
Upending the cliché of muscleheads, scientists at the Laboratory of Neuroscience at the National Institute on Aging recently set out to examine whether changes in muscles prompted by exercise might subsequently affect and improve the brain’s ability to think.
Lab animals and people generally perform better on tests of cognition after several weeks of exercise training, and studies have shown that over time, running and other types of endurance exercise increase the number of neurons in portions of the brain devoted to memory and learning. But the mechanisms that underlie this process remain fairly mysterious. Do they start within the brain itself? Or do messages arrive from elsewhere in the body to jump-start the process?
Gretchen Reynolds on the science of fitness.
The researchers were especially interested in the possibility that the action starts outside the brain – and specifically in the muscles. “We wondered whether peripheral triggers might be activating the cellular and molecular cascades in the brain that led to improvements in cognition,” says Henriette van Praag, the investigator at the National Institute on Aging who led the study.
Muscles are, of course, greatly influenced by exercise. Muscle cells respond to exercise by pumping out a variety of substances that result in larger, stronger muscles. Some of those compounds might be entering the bloodstream and traveling to the brain, Dr. van Praag says.
The problem is that exercise is such a complicated physiological stimulus that it’s very difficult to isolate which compounds are involved and what their effects might be. So she and her colleagues decided to study “fake” exercise instead, using two specialized drugs that had been tested several years ago by scientists at the Salk Institute in San Diego.
The drugs had been shown to induce the same kinds of changes in sedentary animals’ muscles that exercise would cause, so that even though the mice didn’t exercise, they physiologically responded as if they had.One of the drugs that they used, known as Aicar, increases the muscles’ output of AMPK, an enzyme that affects cellular energy and metabolism.
Regular endurance exercise, like running or cycling, increases the muscles’ production of this enzyme. In the Salk experiments, Aicar enabled untrained mice to run 44 percent farther during treadmill tests than other, sedentary animals that hadn’t received the drug.
The second compound, GW1516, a cholesterol drug, also stimulates biochemical changes in muscle cells like those caused by endurance exercise. But in the Salk studies, it had amplified endurance primarily in animals that also ran, allowing them to run farther than another set of running mice that didn’t get the drug. But it hadn’t done much muscle-wise for animals that remained sedentary.
By using these drugs in unexercised animals under well-controlled conditions, the scientists from the National Institute on Aging sought to determine whether changes in muscles then initiated changes in the brain.
And as it turned out, muscles did affect the mind. After a week of receiving either of the two drugs (and not exercising), the mice performed significantly better on tests of memory and learning than control animals that had simply remained quiet in their cages. The effects were especially pronounced for the animals taking Aicar.
The results, published in the journal Learning and Memory, showed that the drugged animals’ brains also contained far more new neurons in brain areas central to learning and memory than the brains of the control mice, an effect found by microscopic examination.
Because the two drugs “don’t cross the blood-brain barrier much, if at all,” Dr. van Praag says, “we could be fairly confident that the changes we were seeing were related to an exercise-type reaction in the muscles” and not to brain responses to the drugs.
The message of this finding, she continues, is that “improvements in cognition” that follow exercise “would seem to involve changes throughout the body and not just in the brain.”
Although the exact process isn’t clear, Dr. van Praag speculates that some of the AMPK enzyme created during exercise enters the bloodstream and travels to the brain, setting off a series of new reactions there.
The implication, she continues, is that exercise may need to be aerobic if it’s going to substantially affect the brain. “You probably need to increase blood flow, which mostly occurs during endurance training,” she says. Also, in animal studies, AMPK production has been found to increase principally after running. Of course, “it’s very hard for us to study weight lifting in mice,” Dr. van Praag says, so it’s possible that other types of exercise might improve AMPK production and cognition too, she says.
Interestingly, when the scientists continued injecting mice with Aicar for an additional week, the animals’ brains stopped responding. They actually began losing their augmented ability to learn, compared with the control animals, a finding that suggests, Dr. van Praag says, that drugs may be an unsatisfactory — and potentially detrimental — way to emulate the effects of exercise.
Exercise, on the other hand, is generally safe. “And the scientific evidence, including ours,” she says, “is strong and growing that it is very good for the muscles — and for the brain.”
Gretchen Reynolds is the author of “The First 20 Minutes: Surprising Science Reveals How We Can Exercise Better, Train Smarter, Live Longer” (Hudson Street Press, 2012).
The Surprising Shortcut to Better Health
Books | By TARA PARKER-POPE |
Perhaps
the most unexpected message from the new fitness book “The First 20
Minutes” is not that we all need to exercise more to achieve better
health. We just need to do something.
For more than a decade, Gretchen Reynolds has been writing about the science of health and fitness. Her weekly column, Phys Ed, is one of this paper’s most popular features, regularly appearing on top of the “Most E-mailed” list. Now Ms. Reynolds has distilled the knowledge gained from years of fitness reporting into a new book, “The First 20 Minutes: Surprising Science Reveals How We Can Exercise Better, Train Smarter, Live Longer,’’ published last month.
While the subtitle alone makes bold promises about the potential of
exercise to protect the human body, the most surprising message from Ms.
Reynolds is not that we all need to exercise more — or at least not the
way exercise is typically defined by the American public. Ms. Reynolds
makes a clear distinction between the amount of exercise we do to
improve sports performance and the amount of exercise that leads to
better health. To achieve the latter, she explains, we don’t need to run
marathons, sweat it out on exercise bikes or measure our peak oxygen
uptake. We just need to do something.
“Humans,” she writes, “are born to stroll.”
I recently spoke with Ms. Reynolds about the science of exercise, why standing up is good for you and why, after writing a book about fitness, she began to exercise less. Here’s our conversation.
Without being evangelical, I wanted people to understand that this is a book about how little exercise you can do in order to get lots and lots of health benefits. Two-thirds of Americans get no exercise at all. If one of those people gets up and moves around for 20 minutes, they are going to get a huge number of health benefits, and everything beyond that 20 minutes is, to some degree, gravy.
That doesn’t mean I’m suggesting people should not exercise more if they want to. You can always do more. But the science shows that if you just do anything, even stand in place 20 minutes, you will be healthier.
If you are overweight but fit, meaning you have a reasonably good V012 max (a measure of oxygen uptake), then your risk of premature death, all the chronic diseases — diabetes, heart disease, cancer — will drop. If you have to choose, choose to be fit, whether you lose weight or not.
If someone starts an exercise program and improves his fitness, even if he doesn’t lose an ounce, he will generally have a longer life and a much healthier life. It would be nice if people would look at exercise as a way to make themselves feel better and live longer and not necessarily as a way to make themselves skinnier.
I also exercise a whole lot less. Partly it’s because I have less time, but it’s also because I have learned that I don’t have to do more to be healthy. My main goal now is not to be competitive. What I really want is to be healthy and to set a good example for my son. I want to be around for the next 40 years, and the science seems to show very clearly that you don’t have to do a lot to make yourself a whole lot healthier.
I run a couple of miles most days. I used to feel like if I didn’t run five miles it didn’t count. Now I’m very content to get out for half an hour or 20 minutes, and I feel reasonably healthy after that.
There are always options for moving. You don’t have to do anything that hurts. You don’t have to buy equipment. If you have a pair of shoes, they don’t even have to be sneakers. People have gotten the idea that exercise has to be complicated, and that they need a heart rate monitor, and a coach, and equipment and special instruction. They don’t.
The human body is a really excellent coach. If you listen to it, it will tell you if you’re going hard enough, if you’re going too hard. If it starts to hurt, then you back off. It should just feel good, because we really are built to move, and not moving is so unnatural. Just move, because it really can be so easy, and it really can change your life.
Russell Thurston Gretchen Reynolds
For more than a decade, Gretchen Reynolds has been writing about the science of health and fitness. Her weekly column, Phys Ed, is one of this paper’s most popular features, regularly appearing on top of the “Most E-mailed” list. Now Ms. Reynolds has distilled the knowledge gained from years of fitness reporting into a new book, “The First 20 Minutes: Surprising Science Reveals How We Can Exercise Better, Train Smarter, Live Longer,’’ published last month.
“Humans,” she writes, “are born to stroll.”
I recently spoke with Ms. Reynolds about the science of exercise, why standing up is good for you and why, after writing a book about fitness, she began to exercise less. Here’s our conversation.
Q.
Why did you choose “The First 20 Minutes” for the title of a fitness book?
A.
The first 20 minutes of moving around, if someone has been really
sedentary, provide most of the health benefits. You get prolonged life,
reduced disease risk — all of those things come in in the first 20
minutes of being active.Without being evangelical, I wanted people to understand that this is a book about how little exercise you can do in order to get lots and lots of health benefits. Two-thirds of Americans get no exercise at all. If one of those people gets up and moves around for 20 minutes, they are going to get a huge number of health benefits, and everything beyond that 20 minutes is, to some degree, gravy.
That doesn’t mean I’m suggesting people should not exercise more if they want to. You can always do more. But the science shows that if you just do anything, even stand in place 20 minutes, you will be healthier.
Q.
Is part of the problem that people equate exercise with trying to lose weight, and many of them have given up?
A.
I think a lot of people look to exercise to help them lose weight,
and when they don’t lose weight immediately with exercise, they quit.
They return to the couch, and they basically never move again. What is
lost in that is that fitness is almost certainly more important than
fatness.If you are overweight but fit, meaning you have a reasonably good V012 max (a measure of oxygen uptake), then your risk of premature death, all the chronic diseases — diabetes, heart disease, cancer — will drop. If you have to choose, choose to be fit, whether you lose weight or not.
If someone starts an exercise program and improves his fitness, even if he doesn’t lose an ounce, he will generally have a longer life and a much healthier life. It would be nice if people would look at exercise as a way to make themselves feel better and live longer and not necessarily as a way to make themselves skinnier.
Q.
In researching this book, what did you find are the biggest misconceptions about exercise?
A.
One of the biggest misconceptions is that exercise has to be hard,
that exercise means marathon running or riding your bike for three hours
or doing something really strenuous. That’s untrue and, I think,
discourages a lot of people from exercising. If you walk, your body
registers that as motion, and you get all sorts of physiological changes
that result in better health. Gardening counts as exercise. What would
be nice would be for people to identify with the whole idea of moving
more as opposed to quote “exercise.”
Q.
A regular theme of your column is the risks of being sedentary. What’s more important to health: exercise or sedentary behavior?
A.
It’s also an important theme in the book. There are two things going
on: One is activity, and the other is inactivity, and they have
different effects on the body. There is a whole scientific discipline
called inactivity physiology that looks at what happens if you just sit
still for hours at a time. If the big muscles in your legs don’t
contract for hours on end, then you get physiological changes in your
body that exercise won’t necessarily undo. Exercise causes one set of
changes in your body, and being completely sedentary causes another.
Q.
Has writing this book changed your own approach to fitness?
A.
It validated some of the things I was already doing, like not
stretching before a workout, which I always hated doing. I hated sit-ups
and found out they were bad for your back. I was pleased to learn that.
It has changed how I approach hydration in exercise. Now I drink when
I’m thirsty, and it seems to be completely fine.I also exercise a whole lot less. Partly it’s because I have less time, but it’s also because I have learned that I don’t have to do more to be healthy. My main goal now is not to be competitive. What I really want is to be healthy and to set a good example for my son. I want to be around for the next 40 years, and the science seems to show very clearly that you don’t have to do a lot to make yourself a whole lot healthier.
I run a couple of miles most days. I used to feel like if I didn’t run five miles it didn’t count. Now I’m very content to get out for half an hour or 20 minutes, and I feel reasonably healthy after that.
Q.
And you told me that you also stand more?
A.
I really do stand up at least every 20 minutes now, because I was
spending five or six hours unmoving in my chair. The science is really
clear that that is very unhealthy, and that it promotes all sorts of
disease. All you have to do to ameliorate that is to stand up. You don’t
even have to move. I’m standing up right now as I talk on the phone. I
stand during most of my interviews now.
Q.
I’m finding this very inspirational. What is your advice for people reading this — what should they go do today?
A.
If people want to be healthier and prolong their life span, all they
really need to do is go for a walk. It’s the single easiest thing anyone
can do. There are some people who honestly can’t walk, so I would say
to those people to try to go to the local Y.M.C.A. and swim.There are always options for moving. You don’t have to do anything that hurts. You don’t have to buy equipment. If you have a pair of shoes, they don’t even have to be sneakers. People have gotten the idea that exercise has to be complicated, and that they need a heart rate monitor, and a coach, and equipment and special instruction. They don’t.
The human body is a really excellent coach. If you listen to it, it will tell you if you’re going hard enough, if you’re going too hard. If it starts to hurt, then you back off. It should just feel good, because we really are built to move, and not moving is so unnatural. Just move, because it really can be so easy, and it really can change your life.
Paul Conrath/Getty Images
Mixing Weight Training and Aerobics
Phys Ed | By GRETCHEN REYNOLDS
Many
competitive athletes and trainers believe that aerobic exercise and
strength training should not be done in close proximity, but two new
studies show that both can be done, in either order, without dampening
the overall benefits of each.
The Evolution of the Runner’s High
Phys Ed | By GRETCHEN REYNOLDS |
Alain Daussin/Getty Images
People
and dogs experience runner’s high. Ferrets don’t. New findings may help
explain why aerobic exercise appears to be part of our evolutionary
history.
Read more…
Read more…
Jogging Your Brain
Fitness | By TARA PARKER-POPE |
Exercise, the latest neuroscience suggests, does more to bolster thinking than thinking does. Read more…
Does Exercise Make You Overeat?
Phys Ed | By GRETCHEN REYNOLDS |
Getty Images
Exercise may change your desire to eat, two recent studies show, by
altering how certain parts of your brain respond to the sight of food. Read more…
How Exercise Can Prime the Brain for Addiction
Phys Ed | By GRETCHEN REYNOLDS |
Martin Strattner/Getty Images
An
eye-opening new study of cocaine-addicted mice found that dedicated
exercise may in some cases make it even harder to break an addiction.
Meet the Active Couch Potato
Phys Ed | By GRETCHEN REYNOLDS |
Volunteers
in a study spent just as much time sitting on days when they exercised
as they did on days off, a habit that may be deadly. Read more…
Perception and Peak Performance
By GRETCHEN REYNOLDS |
Manipulate equipment or expectations so that a task looks easy and, the work of one psychologist suggests, it will be. Read more…
Making the Case for Running Shoes
Phys Ed | By GRETCHEN REYNOLDS |
Barefoot running, often touted by fans as more natural than wearing shoes, may actually be less metabolically efficient. Read more…
Do Statins Make It Tough to Exercise?
By GRETCHEN REYNOLDS |
Statins,
the most widely prescribed drugs in the world, can cause muscle aches
and fatigue, and the effects may be especially pronounced in people who
exercise. Read more…
Getting Fat but Staying Fit?
By GRETCHEN REYNOLDS |
Exercise by itself won’t erase the heart risks of extra body fat, but it may blunt them. Read more…
Why It’s So Important to Keep Moving
By GRETCHEN REYNOLDS |
Inactivity
produced spikes in blood sugar levels in healthy young volunteers,
which may help explain why sedentary behavior raises the risk of Type 2
diabetes and heart disease. Read more…
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