Transcript Exercise_Effects_on_the_brain

Exercise and the Brain
Karen Lindgren, Ph.D.
Our Mission
To ensure that every person is given opportunities for lifelong learning
and fulfillment.
We do this by altering perceptions, and by supporting those with
intellectual and developmental challenges and acquired brain injuries in
achieving their life goals as valued and respected members of our world.
Our Core Values
Responsible Empathetic Supportive Passionate Empowered Committed Trustworthy
RESPECT
Our Vision
By 2014 our distinct ability to deliver high quality individualized services in
modern living, learning and working environments will exceed stakeholder
expectations and secure Bancroft as the region’s elite provider of services to
people with intellectual and developmental disabilities and brain injuries.
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Strength of mind is exercise, not rest
-Alexander Pope
It is exercise alone that supports the
spirits, and keeps the mind in vigor
- Marcus Tullius Cicero
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Goals
• How does exercise benefit general health?
• How does exercise benefit neurological
health?
• What are specific cognitive benefits of
exercise?
• What is neuroplasticity?
• How does exercise benefit neuroplasticity?
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Format
• GEOGRAPHY OF THE BRAIN
• WHAT IS NEUROPLASTICITY
• EXERCISE
o What it is
o Physiology
• EXERCISE AND THE BRAIN
o Simple connections
o Complex connections
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The link should be clear
• Our brain is a physical organ
• Our brain is a thinking organ
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The link should be clear
Exercise helps us physically
• strengthens: hearts, bones, lungs, blood vessels
• physical changes should be related to thinking
changes
Like our other organs, our brain is a constantly
changing organ
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The brain: physical organ
Geography of the brain
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Brain basics
Neurons
Blood vessels
Neurotransmitters
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The brain: a thinking organ
What is thinking?
• Cognition refers to any mental process
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What is cognition?
Areas of cognition include:
• Attention
• Concentration
• Sensory skills
• Motor skills
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What is cognition?
Areas of cognition include:
• Language
• Visual Skills
• Memory
• Problem solving/judgment moral reasoning
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Brain Geography
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Neuroplasticity
What is neuroplasticity?
• Refers to the ability of the brain to shape itself
according to experience
• Refers to physical change on a neuronal level
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Neuroplasticity
What changes when we learn?
• Neurons connect with other neurons
• Synapses strength changes with learning
• More synapses form between neurons
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What is exercise?
Types
• Cardiovascular
• Weight training (resistance training)
Intensity
• Active lifestyle
• Light
• Vigorous
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What happens when we exercise?
Heart rate increases
Hormones respond
• Pituitary gland releases human growth
hormone to increase production of bone,
muscle, or connective tissue cells.
Pituitary gland regulates
• Thyroid
• Adrenal
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Pituitary Gland
• Located in brain, limbic system
• Influences:
o Thyroid: neck
o Adrenal: kidneys
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What happens when we exercise?
Hormones respond
• Pituitary gland regulates thyroid gland
Thyroid: releases hormones
• Increase heart rate and blood pressure
• Regulate body temperature
• Elevate “alertness” in brain to increase
concentration and reaction time
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What happens when we exercise?
Hormones respond
• Pituitary gland regulates
o Adrenal glands: In response to the ACTH
(adrenocorticotropin) from the pituitary, release
o 1. cortisol: causes blood pressure to rise, triggers
increase in glucose, acts as anti-inflammatory
agent (repairs tissues) Curbs non-critical
functions (e.g., thirst, urine, hunger). Effects
immune system.
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What happens when we exercise?
Hormones respond
• Pituitary gland regulates
o Adrenal glands: In response to the ACTH
(adrenocorticotropin) from the pituitary, release
o 2. aldosterone: bodily response to anticipate
dehydration through impact on kidney function.
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What happens when we exercise?
Hormones respond
• Pituitary gland regulates
o Adrenal glands: In response to the ACTH
(adrenocorticotropin) from the pituitary, release
o 3. adrenaline (fight or flight) mechanism. A
stimulant, increases strength and frequency of
heart contractions. Speeds breakdown of stored
carbs into glucose for muscle energy.
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Section Break
• GEOGRAPHY OF THE BRAIN
• WHAT IS NEUROPLASTICITY
• EXERCISE
o What it is
o Physiology
• EXERCISE AND THE BRAIN
o Simple connections
o Complex connections
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Exercise and the Brain:
How do we know they are linked
Studies vary greatly (meta-analysis,
Kramer et al)
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Ages vary
Length of time looked at varies
Exercise type varies
Method of reporting varies (often self-report)
Method of reporting cognitive skill varies (e.g., MMSE
screen, neuropsych, presence of dementia)
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What is the link?
Simple links
• Increased blood flow to the brain is good for us
• Simple mind/body benefits: mindfulness
training, yoga
Complex links
• Neuroplasticity
• Preventing problems
• Improved mood--- improved thinking
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Simple connections
• Exercise improves blood flow to the brain
• Is increased blood flow related to improved
cognition?
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Simple connections
Physical effects of exercise
• Increased blood flow to the brain
o Blood volume increases
o Blood flow is more “predictable”
o Small vessels grow – increase in number
• Study of 16 women aged 60 and older, walking
briskly 3-4 times per week, improved blood
flow up to 15 %
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Simple connections
Physical effects of exercise
• Brings O2, glucose, nutrients to brain cells, vital
for cell health
• Cell growth: supports new connections,
particularly in hippocampus- memory
• Blood washes away “metabolic wastes” such as
“amyloid beta protein” (implicated in
development of Alzheimers)
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Simple connections
Walking:
• Increases blood circulation
• Increased oxygen and glucose to the brain
• Not strenuous- muscles do not use extra oxygen
and glucose as in more strenuous exercise
In sum, you oxygenate your brain
“Clear your head”
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Complex Links
Complex links
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Prevents primary neurologic disease
Promotes healthy normal aging
Neuroplasticity
Improved mood--- improved thinking
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Exercise prevents primary
neurologic disease
Primary Neurologic Disease
• Vascular disease
o Cholesterol lowering effects of exercise
o Exercise lowers blood pressure:
 High blood pressure is related to stroke and
mild cognitive impairment
o Increased blood flow
o Increased vessels
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Exercise promotes healthy aging
Normal Aging
• Ameliorates decline: Canadian researchers1 examined
active lifestyle for “elderly” individuals over 2-5 years,
showed stability in cognitive functioning for individuals
who were active, greater change if sedentary.
• 90% of individuals with greatest daily energy scored
consistently on tests each year
• Activities included walking, cooking, cleaning
1. Archives of Internal Medicine, 2011
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Exercise promotes healthy aging
Normal Aging
• More specifically, women in 70’s with vascular
disease showed a slower rate of cognitive
decline than the active group. Editorial (Dr.
Eric Larson) noted the goal was to slow the
onset of dementia.
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Exercise promotes healthy aging
Normal Aging
• A second study2 showed that light duty weight
training has neurological effects.
• After one year, older women who lifted 2x per
week showed changes on both functional MRIs
and cognitive tests.
2. Neurobiology of Aging, 2011
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Exercise promotes healthy aging
Normal Aging: start early!
• Mayo clinic study of 1,126 individuals with
“normal cognition” (as opposed to Mild
cognitive impairment)3
• Individuals with Moderate exercise during
midlife were less likely to develop impairment in
later life
3. Archives of Neurology, 2011
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Exercise promotes healthy aging
• Exercise prevents onset of dementia
• Meta analysis of 1600 research papers
examining role of exercise in perserving
cognitive abilities
• Conclusion: Important therapy against dementia
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Exercise promotes healthy aging
“…you can make a very compelling argument for
exercise as a disease-modifying strategy to prevent
dementia and mild cognitive impairment, and for
favorably modifying these processes once they
have developed.”
-- J. Eric Ahlskog, M.D., Ph.D., neurologist, Mayo Clinic
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Exercise promotes healthy aging
Other Neurologic Disease
• Parkinson’s Disease
o Researchers4 followed 140,000 people with avg. age of
63 for 10 years.
o Moderate to vigorous activity levels were related to a
40% less chance to develop Parkinsons than those with
light or no activity levels.
o Not clear if the relationship is focused on short term
or long term (i.e., do you need to start exercising at 40?)
4. American Academy of Neurology, 2007
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Exercise promotes healthy aging
Other Neurologic Disease
• Mild cognitive impairment (MCI): each year, 10-15% of
individuals with mild cognitive impairment will develop
dementia5.
• Study: 33 adults with MCI. 23 assigned randomly to
aerobic group and exercised at high intensity levels for
45-60 minutes per day, 4 days per week, with a trainer.
Control group: 10 individuals performed supervised
stretching with low heart rate.
5. Archives of Neurology, 2011
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Exercise promotes healthy aging
Other Neurologic Disease
• Found improved fitness (body fat analysis,
metabolic markers) and improved cognition.
• Cognitive improvements were more marked in
women than men. This may be related to body’s
use of insulin, glucose, and cortisol, which
differed between the sexes.
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Exercise and Stress
• Chronic cortisol release leads to detrimental
effects:
o Chronically high cortisol reduces dopamine
• Exercise initially mimics this effect
• Regular exercise training helps to reduce cortisol
levels (e.g., a 20 minute walk ceases to be
“stressful” to the body).
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Mood Benefits
Exercise improves stress tolerance:
• Exercise causes a drop in stress hormones
• Improves “resilience” to stress
• Brain-derived neurotrophic factors (BDNF)
o “fertilizer” of the brain’s neurons
o Grow more quickly, develop stronger connections
o Associated with improved cognition, mood
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Mood Benefits
Exercise improves stress tolerance:
• Rats assigned to 4 groups6:
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Engaged in “voluntary running”
Given antidepressants
Both
Neither
• Rats then underwent a 2-day “forced swimming”
procedure
6. California State University, 2001
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Mood Benefits
Exercise improves stress tolerance:
• Results:
o BDNF levels in untreated animals were depressed
o Animals that were given physical training or
antidepressants had BDNF restored to baseline
o Animals with both showed increase in
hippocampal BDNF well above baseline.
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Mood Benefits
Improved mood improves cognition:
• Exercise has an “antidepressant effect”
• Antidepressant effect of running was associate
with more cell growth in hippocampus9
9. Proceedings of the Academy of Natural Sciences, 2010
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Does exercise foster
neuroplasticity?
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Exercise increased growth factors in brain making it easier
to grow new connections10
Mice that ran on a wheel had twice as many new brain cells
as mice housed in standard cages11. As a comparison,
provided mice with other “enriched” environments (e.g.,
“free swim”)- only running produced the effect.
o Growth was in the hippocampus (learning and
memory)
10. UCLA, 2011
11. Nature Neuroscience, 1999
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Does exercise foster
neuroplasticity?
• Illinois researchers scanned brains of 55 individuals
aged 55-79, measured maximal O2 during exercise12
• Used MRIs and functional imaging to examine agerelated brain shrinkage
• Results: fit subjects had less shrinkage in temporal,
parietal, and frontal areas- crucial for learning and
memory
12. Journal of Gerontology, 2003
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Does exercise foster
neuroplasticity?
• Meta-analysis of 18 controlled studies of
cognitive function and aerobic fitness for
individuals aged 55-8013
13. Psychological Sciences, 2003
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Does exercise foster
neuroplasticity?
Results:
• Exercise had clear, selective cognitive benefits for
attention, organization, planning
• Frontal skills
• Strength training combined with aerobic fitness was
most effective
• Exercise sessions of less than 30 minutes per session
had little impact
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Does exercise foster
neuroplasticity?
• Brain-derived neurotrophic factors (BDNF)
• “fertilizer” of the brain’s neurons
o Grow more quickly, develop stronger connections
• Associated with improved cognition, mood
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Does exercise foster
neuroplasticity?
• Brain-derived neurotrophic factors (BDNF)
• produced in the brain during endurance training
• produced peripherally in resistance training, circulates
to the brain
• University of Florida study: 20 college aged men14
o Increased neurotrophic factors at 1, 30 and 60 minutes
after endurance training
14. American College of Sports Medicine, 2010
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Cognitive exercise
• Cognitive exercise has similar effects
• Two together have strongest effects
• Visualizing exercise improves neuroplasticity
as well
• Best exercise is novel tasks: at any level
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Yoga is cognitive and physical
• Yoga, mind/body connection is good for us
• Yoga decreases depression, anxiety,
hypertension, stress
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Yoga is cognitive and physical
Yoga: the research
• Enhanced effects of meditation alone
• Study of novice participants in a 12-week
yoga training program15
15. Journal of Alternative and Complementary Medicine, 2009
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Yoga is cognitive and physical
Results:
• EEG changes were greater in left hemisphere
• Participants experienced greater ability to activate
their brain, particularly right hemisphere, through
yoga
• Increased blood flow in right pre-frontal cortex
• Changes in amygdala, sensorimotor cortex consistent
with changes in processing emotions and sensory
phenomena
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Conclusions
• Cognition is complex
• MIND-MOOD-BRAIN all connected to
health
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Conclusions
Exercise is shown to positively affect cognition in
the following ways:
• Improving blood circulation
• Increased availability of oxygen and nutrients
• Clears metabolic waste
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Conclusions
Exercise prevents disease:
• Cardiovascular effects decrease risk of stroke
• Shown to prevent Alzheimers, Parkinsons,
mild cognitive impairment onset
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Conclusions
• Regular exercise decreases our symptoms of
stress (e.g., lowers cortisol)
• Improves resiliency
• Improves mood- acts as an antidepressant
• Increases growth of neurons in key areas:
o Frontal lobes, hippocampus
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Practical Advice
The Basics:
• Do something
• Stick with what you stick with
• Every bit counts: even 20 minutes of exercise
facilitates brain function
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Practical Advice
The Details:
• Exercise has short term effects of mood,
concentration, memory and stress that last for
several hours after exercise
• Moderate exercise for a six month time frame
is beneficial to begin to see long term benefits
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Practical Advice
The Details:
• Exercise should continue with age
• Exercise that encourages cognitive focus has
additional benefits : find something that
challenges you (ballroom dancing, a new class,
yoga, etc.)
• Exercise that is interesting is also good (vary
your walk!)
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Special Information: Brain Injury
Exercise after concussion is not
recommended:
• REST IS RECOMMENDED
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Special Information: Brain Injury
For all these reasons, exercise is important for
long term recovery from a brain injury
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Promotes mood
Promotes stable sleep patterns
Promotes physical health
Promotes self-efficacy, improved views of health
Promotes neurogenesis in animal models
Increased blood flow in hippocampus
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Special Information: Brain Injury
For all these reasons, exercise is important for
long term recovery from a brain injury
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Promotes mood
Promotes stable sleep patterns
Promotes physical health
Promotes self-efficacy, improved views of health
Promotes neurogenesis in animal models
Increased blood flow in hippocampus
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Questions?
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Thank you for joining us!
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