tones the legs, builds bigger biceps and strengthens the
heart. But of all the body parts that benefit from a good
workout, the brain may be the big winner.
fitness directly affects our mind and plays a crucial role in
the way the brain develops and functions. Moreover, exercise
is linked to brain changes throughout all stages of life,
beginning in infancy and lasting through old age.
for example, need regular movement to carve out critical
pathways and form connections in the brain. In children,
research suggests exercise improves attention, focus and
academic performance. And in the elderly, exercise has been
shown to help stave off memory loss associated with some forms
of dementia, including Alzheimer’s disease.
activity is crucial to mind and body alike," said
neuroscientist Lise Eliot, who writes about the benefits of
movement on the brain in her book "Pink Brain, Blue
Brain." "The brain benefits as much as the heart and
other muscles from physical activity."
used to believe the mind-body connection was a one-way street:
The brain helped build a better physique — or else it
sabotaged attempts to get to the gym. But scores of studies
suggest that what’s good for the body also is nurturing the
old noodle. Exercise, it turns out, can help improve cognition
in ways that differ from mental brain-training games.
found exercise has broad benefits on cognition, particularly
executive functioning, including improvements in attention,
working memory and the ability to multitask," said
researcher Charles Hillman, a professor of kinesiology and
community health at the University of Illinois at
Urbana-Champaign. In fact, an active lifestyle during
childhood may confer protective effects on brain health across
the life span, Hillman said.
exercise help the brain?
mid-1990s, Carl Cotman’s team at the University of
California-Irvine first showed that exercise triggers the
production of a protein called brain-derived neurotrophic
factor, or BDNF, which helps support the growth of existing
brain cells and the development of new ones.
age, BDNF levels fall; this decline is one reason brain
function deteriorates in the elderly, according to Cotman.
Certain types of exercise, namely aerobic, are thought to
counteract these age-related drops in BDNF and can restore
young levels of BDNF in the aging brain.
a sense, BDNF is like a brain fertilizer," said Cotman, a
professor of neurology and neurobiology and behavior and
founding director of the Institute for Memory Impairments and
Neurological Disorders (UCI Mind). "BDNF protects neurons
from injury and facilitates learning and synaptic
last two decades, researchers have learned that exercise acts
on multiple levels in the brain. The brain’s wiring depends
on the integrity of the brain cells or neurons, as well as the
connections between the neurons, or the synapses.
age, the synapses are lost or break down. Cotman’s work has
shown that in older rodents, exercise increases the number of
synapses and also stimulates the brain to develop more neurons
in the hippocampus, which he called "a critical region in
learning and memory formation and a target of massive decline
in Alzheimer’s disease."
for those newly created brain cells, or neurons, to work —
to help us learn and remember new things — they need to be
plugged into the existing neural network, said Romain Meeusen,
chair of the department of human physiology at the University
helps integrate the new neurons into the brain’s circuitry
to help improve learning, Meeusen said.
general, exercise increases the release of neurotransmitters,
or brain chemicals that relay signals between nerve cells,
called neurons, Meeusen said. "This could be one of the
mechanisms of the anti-depressive effect of exercise," he
said. "It also helps to ‘train’ cognition and
attention at all ages."
also suggests that exercise improves blood flow to the brain
and, as a result, enhances cognitive abilities. "The
blood carries oxygen and feeds neural tissues, so you’re
getting the benefits that come with that," Hillman said.
brain loves it when we move and will reward us handsomely if
we do, researchers say. Here’s a look at how physical
activity can be beneficial during three key stages of life.
children hit their cognitive milestones faster, said Eliot, an
associate professor of neuroscience at Rosalind Franklin
University’s Chicago Medical School.
infants are awake, they’re in near-constant motion, which is
critical for development, Eliot said. This movement
"strengthens their muscles and hones their neural
circuits for smooth, purposeful motor skills."
process continues throughout life but is obviously most
intense in infancy and toddlerhood, when children are
mastering brand-new skills like sitting, standing, walking,
running and jumping, Eliot said.
worries that babies in the U.S. are spending too much time
strapped in devices. Like adults trying to master a new sport,
"young children need to practice to speed their neural
pathways and select the optimal circuits to hone each
milestone," Eliot said.
In a new
twist in the debate over physical education in schools,
researchers are asking an intriguing question: What if
exercise improves academic success?
research suggests it can. Hillman’s team at the University
of Illinois’ Neurocognitive Kinesiology Laboratory found
that children aged 7 through 9 who participated in a 60-minute
after-school exercise program had better focus, processed
information more quickly and performed better on cognitive
tests than children who didn’t exercise.
researchers also found a dose effect: The more days the
children attended the exercise program, the greater the
changes in their brain function or cognition, according to the
nine-month randomized trial, published in the journal
Pediatrics in 2014.
didn’t take low-fit kids and make them highly fit,"
Hillman said. "We took low-fit kids and made them a
little less low fit. These aren’t massive changes."
effects were seen only on tasks that required executive
control, "which is related to attention, behavior and
obviously germane to success in school," Hillman said.
our working memory and cognitive flexibility — often called
multitasking — the ability to take information, put it on
hold and go back and forth."
the hippocampus naturally shrinks in late adulthood, leading
to impaired memory and increased risk for dementia.
research suggests aerobic exercise can increase the size of
the hippocampus and increase levels of a protein that aids the
growth of new brain cells, potentially holding off changes in
the brain and improving memory function.
of the hippocampus in later life is generally considered
inevitable," said Kirk Erickson, professor of psychology
at the University of Pittsburgh. "But we’ve shown that
even moderate exercise for one year can increase the size of
that structure. The brain at that stage remains
another study, researchers from the University of Wisconsin
School of Medicine and Public Health found that people who
said they exercised for 30 minutes five times a week in
late-middle age did better on cognitive tests and showed less
accumulation of the beta amyloid plaque, the protein that
builds up in the brains of people with Alzheimer’s disease.
ages, active people did better on immediate memory and visual
spatial tests and had less amyloid plaque, better brain
glucose metabolism and higher hippocampus volume compared with
inactive people, according to the research, published in 2014
the journal Neurology.