The neurobiological effects of physical exercise are numerous and involve a variety of interrelated effects on brain structure, brain function, and cognition. Large numbers of human studies have shown that consistent aerobic exercise (eg, 30 minutes daily) induces persistent improvement in certain cognitive functions, healthy changes in brain expression of the gene, and favorable forms of neuroplasticity and plasticity behavior; some of these long-term effects include: increased neuronal growth, increased neurological activity (eg, c-Fos and BDNF signaling), increased coping of stress, improved cognitive behavioral control, declarative, spatial and memory enhancement work, and structural and functional improvements in brain structures and pathways associated with cognitive and memory control. The effects of exercise on cognition have important implications for improving academic performance in children and college students, increasing adult productivity, preserving cognitive function in old age, preventing or treating certain neurological disorders, and improving overall quality of life.
In healthy adults, aerobic exercise has been shown to induce temporary effects on cognition after one practice session and a persistent effect on cognition after regular exercise for several months. People who regularly perform aerobic exercise (eg running, jogging, brisk walking, swimming, and cycling) have greater scores on neuropsychological function and performance tests that measure certain cognitive functions, such as attention control, inhibitory control, cognitive flexibility, memory work updates and capacity, declarative memory, spatial memory, and information processing speed. The temporary effects of exercise on cognition include improvements in most executive functions (eg, attention, work memory, cognitive flexibility, inhibition control, problem solving, and decision making) and processing speed information for a period of up to 2 hours after exercise.
Aerobic exercise induces short-term and long-term effects on mood and emotional states by promoting positive influences, inhibiting negative effects, and reducing biological responses to acute psychological stress. During the short term, aerobic exercise works well as antidepressants and euphoriants, while consistent exercise results in general improvements in mood and self-esteem.
Regular aerobic exercise improves symptoms associated with various central nervous system disorders and may be used as adjunctive therapy for this disorder. There is clear evidence of the efficacy of exercise therapy for major depressive disorder and attention deficit hyperactivity disorder. The American Academy of Neurology's clinical practice guidelines for mild cognitive impairment suggest that physicians should recommend regular exercise (twice per week) to individuals who have been diagnosed with this condition. A review of clinical evidence also supports the use of exercise as an adjunctive therapy for certain neurodegenerative disorders, particularly Alzheimer's disease and Parkinson's disease. Regular exercise is also associated with a lower risk of developing neurodegenerative disorders. A large amount of preclinical evidence and emerging clinical evidence support the use of exercise therapies to treat and prevent the proliferation of drug addictions. Regular exercise has also been proposed as an adjunctive therapy for brain cancer.
Video Neurobiological effects of physical exercise
Long-term effects
Neuroplasticity
Neuroplasticity is a process in which neurons adapt to disorders over time, and most commonly occur in response to repeated exposure to stimuli. Aerobic exercise increases the production of neurotrophic factors (eg, BDNF, IGF-1, VEGF) that mediate improvements in cognitive function and various forms of memory by promoting the formation of blood vessels in the brain, adult neurogenesis, and other forms of neuroplasticity. Consistent aerobic exercise for several months induced a clinically significant increase in executive function and increased gray matter volume in almost all areas of the brain, with the most striking increase occurring in areas of the brain causing executive function. The brain structures that show the greatest increase in the volume of gray matter in response to aerobic exercise are the prefrontal cortex, the caudate nucleus, and the hippocampus; Less significant increases in gray matter volume occur in the anterior cingulate cortex, parietal cortex, cerebellum, and nucleus accumbens. The prefrontal cortex, the caudate nucleus, and the anterior cingulate cortex are among the most significant brain structures in the dopamine and norepinephrine systems that give rise to cognitive control. Neurogenesis induced by exercise (ie, increased gray volume) in the hippocampus is associated with a measurable increase in spatial memory. Higher physical fitness scores, as measured by max VO 2 , are associated with better executive functioning, faster information processing speeds, and greater gray matter volumes of the hippocampus, the caudate nucleus , and nucleus accumbens. Long-term aerobic exercise is also associated with persistent and beneficial epigenetic changes that increase stress coping, improve cognitive function, and increase neuronal activity ( c-Fos and BDNF signaling).
BDNF signaling
One of the most significant effects of exercise in the brain is the increased synthesis and expression of BDNF, the hormone neuropeptide, in the brain and periphery, resulting in increased signals via tyrosine kinase receptor, receptor tropomiosin kinase B (TrkB). Because BDNF is able to cross the blood-brain barrier, higher peripheral BDNF synthesis also increases BDNF signaling in the brain. The induction-induced increase in brain signaling in BDNF is associated with favorable epigenetic changes, improved cognitive function, increased mood, and increased memory. Furthermore, research has provided much support for the role of BDNF in hippocampal neurogenesis, synaptic plasticity, and neural repair. Engaging in moderate high-intensity aerobic exercise such as running, swimming, and cycling increases BDNF biosynthesis through myokin signals, resulting in a threefold increase in blood plasma and BDNF brain level; The intensity of exercise is positively correlated with the increased magnitude of biosynthesis and BDNF expression. A meta-analysis of studies involving exercise effects at BDNF levels found that consistent exercise simply improves resting BDNF levels as well.
IGF-1 signaling
IGF-1 is a peptide and neurotrophic factor that mediates some of the effects of growth hormone; IGF-1 has its physiological effect by binding to specific receptors of tyrosine kinase, IGF-1 receptor, to control tissue growth and remodeling. In the brain, IGF-1 functions as a neurotrophic factor that, like BDNF , plays an important role in cognition, neurogenesis, and neuronal survival. Physical activity is associated with elevated levels of IGF-1 in blood serum, which is known to contribute to neuroplasticity in the brain due to its capacity to cross the blood-brain barrier and cerebrospinal blood-borne barrier; therefore, one review noted that IGF-1 is a key mediator of adult neurogenesis induced by exercise, while a second review characterizes it as a factor linking "body fitness" with "brain fitness". The amount of IGF-1 released into the blood plasma during exercise is positively correlated with the intensity and duration of exercise.
VEGF signaling
The vascular endothelial growth factor VEGF is neurotrophic and angiogenic (ie, blood vessels that promote growth) a signaling protein binding two tyrosine kinase receptors, VEGFR1 and VEGFR2, expressed in neurons and glial cells in brain. Hypoxia, or inadequate cellular oxygen supply, greatly enhances the regulation of VEGF expression and VEGF provides neuroprotective effects on hypoxic neurones. Like the abnormal brain-derived neurotrophic factors BDNF and Structural growth
A review of neuroimaging research shows that consistent aerobic exercise increases gray matter volumes in almost all areas of the brain, with more apparent increases in brain areas associated with memory processes, cognitive control, motor function, and rewards; the most prominent advantages in the gray matter volume seen in the prefrontal cortex, the caudate nucleus, and the hippocampus, which support cognitive control and memory processing, among other cognitive functions. In addition, the left and right sections of the prefrontal cortex, the hippocampus, and the cingulate cortex appear to be more functionally interconnected in response to consistent aerobic exercise. Three reviews show that marked increases in prefrontal gray matter volume and hippocampus occur in healthy adults who are regularly involved in moderate intensity exercise for several months. Other areas of the brain that exhibit moderate or less significant gains in gray matter volume during neuroimaging include anterior cingulate cortex, parietal cortex, cerebellum, and nucleus accumbens.
Regular exercise has been shown to counter the shrinking hippocampus and memory disorders that naturally occur in late adulthood. Adults who are over 55 years of age show a 1-2% decrease in hippocampal volume annually. A neuroimaging study with a sample of 120 adults revealed that participating in regular aerobic exercise increased left hippocampus volume by 2.12% and the right hippocampus by 1.97% over a one year period. Subjects in low intensity stretch groups who had higher levels of early fitness showed less hippocampal volume loss, providing evidence for exercise that protects against age-related cognitive decline. In general, individuals who exercise more over a given period have larger hippocampal volumes and better memory function. Aerobic exercise has also been shown to induce growth in the white matter tracts in the anterior corpus callosum, which usually shrink with age.
The various functions of brain structures that show the increase triggered by exercise in gray matter volumes include:
- The cingulate prefrontal and anterior cortex - necessary for behavioral cognitive control, particularly: working memory, attention control, decision making, cognitive flexibility, social cognition, and behavioral inhibition control; engaging in attention deficit hyperactivity disorder (ADHD) and addiction
- Nucleus accumbensÃ, - is responsible for the importance of incentives ("desire" or desire, motivational form associated with reward) and positive reinforcement; engage in addiction
- HippocampusÃ, - is responsible for the storage and consolidation of declarative memory and spatial memory; involved in depression
- Cerebellum - responsible for motor coordination and motor learning
- Caudate nucleus - responsible for stimulus-response learning and inhibition control; involved in Parkinson's disease, Huntington's disease and ADHD
- Parietal cortex - responsible for sensory perception, working memory, and attention Long term term effects on cognition
- Brain fitness
- Memory boost
- Nootropic
- Exercise therapy
- Exercise is a Drug
- Recipes exercise
Compatibility with the functional role of brain structures that exhibit an increase in the volume of gray matter, regular exercise for several months has been shown to continuously improve various executive functions and some form of memory. In particular, consistent aerobic exercise has been shown to improve attention control, information processing speed, cognitive flexibility (eg, task shifting), inhibitory control, renewal and work memory capacity, declarative memory, and spatial memory. In healthy young and middle-aged adults, the effect of increasing measures of cognitive function is the largest for the executive and small to medium function indexes for memory and information processing speed. It could be that in older adults, individuals benefit cognitively by taking part in aerobic exercise and endurance at least moderate intensity. Individuals who have less sedentary lifestyles tend to have impaired executive function relative to other more physically active non-exercisers. A reciprocal link between exercise and executive functioning has also been noted: improved executive control processes, such as attention control and inhibitory control, increase the inclination of individuals to exercise.
Maps Neurobiological effects of physical exercise
Short-term effects
Short-term effects on cognition
In addition to the persistent effects of regular exercise for several months on cognitive function, acute exercise (ie, a one-time exercise) has been shown to improve some cognitive function on a temporary basis. Review and meta-analysis of research on the effects of acute exercise in healthy young and middle-aged adults on cognition has concluded that the speed of information processing and a number of executive functions - including attention, working memory, problem solving, cognitive flexibility, verbal fluency, decision making, and inhibitory control - all improving for a period of up to 2 hours post-exercise. A systematic review of studies conducted on children also shows that some of the improvements triggered by exercise in executive function look after one exercise, while other aspects (eg attention control) only increase after regular consistent exercise.
Psychological stress and cortisol
The "stress hormone", cortisol, is a glucocorticoid binding to the glucocorticoid receptor. Psychological stress induces the release of cortisol from the adrenal gland by activating the hypothalamus-pituitary-adrenal axis (HPA axis). Short-term increase in cortisol levels is associated with adaptive cognitive improvement, such as increased inhibition control; however, excessive exposure or prolonged exposure to high levels of cortisol leads to impairment in cognitive control and has neurotoxic effects in the human brain. For example, chronic psychological stress lowers the BDNF expression which has a detrimental effect on hippocampal volume and can cause depression.
As a physical stressor, aerobic exercise stimulates cortisol secretion in a way that relies on intensity; However, it does not result in a long-term increase in cortisol production because the effect induced by exercise on this cortisol is a response to a temporary negative energy balance. Individuals who recently performed exhibit improvements in stress coping behaviors. Aerobic exercise improves physical fitness and decreases neuroendocrine (ie, abacity) and thus reduces the biological response to psychological pressure in humans (eg, reducing the release of cortisol and an attenuated heart rate response). Exercise also reverses the stress-induced decline in brain-derived neurotrophic expression and signaling, thus acting as a buffer against stress-related illnesses such as depression.
Euphoria
Continuous practice can produce short-term euphoria, affective states associated with deep feelings of satisfaction, joy, and well-being, which are known as "high runners " in running distance or " high rower "in rowing. The current medical review shows that some endogenous euphoriants are responsible for generating exercise-related euphoria, especially phenethylamine (endogenous psychostimulant), ? - endorphin (endogenous opioids), and anandamide (endocannabinoid).
Effects on neurochemistry
? - Phenylethylamine
? -Penyenyilenylamine, commonly referred to as phenethylamine, is a human trace amine and a strong catecholaminergic and glutamatergic neuromodulator that has similar psychostimulatory effects and chemical structure to amphetamines. Thirty minutes of moderate to high intensity physical exercise has been shown to cause an extraordinary increase in urine ? - phenylacetic acid , the main metabolite of phenethylamine. Two reviews noted a study in which the average concentration of uric acid - Phenylacetic acid for 24 hours after only 30 minutes of intense exercise increased 77% above the baseline level; the review showed that the synthesis of phenethylamine increased sharply during physical exercise during which it was rapidly metabolized due to a short half-life of about 30 seconds. In a resting state, phenethylamine is synthesized in catecholamine neurons from -phenylalanine by aromatic amino acid decarboxylase at about the same rate at which dopamine is produced.
Given these observations, original papers and reviews both show that phenethylamine plays an important role in mediating the euphoric effects that enhance a runner's high mood, since both phenethylamine and amphetamine are powerful euphoriants.
? - Endorphin
? -Endorphin (contracted from " endo genus mo rphin e") is an endogenous opioid neuropeptide that binds to the -opioid receptor, which in turn produces euphoria and pain relief. A meta-analytic review found that exercise significantly increases the secretion of ? - endorphin and that this secretion is correlated with an improved mood state. Moderate intensity exercise yields the biggest increase in synthesis ? - endorphin , while higher and lower intensity training forms are associated with smaller increases in synthesis ? - endorphin .
A review of ? - endorphin and exercise notes that a person's mood increases for the rest of the day after a physical workout and one's mood is positively correlated with the level of daily physical activity overall. Mental enhancement triggered by exercise occurs in inactive individuals, recreational sportsmen, and marathon runners, but recreational athletes and marathon runners have a more distinct mood lifting effect than exercise.
Anandamide
Anandamide is an endogenous cannabinoid neurotransmitter that binds to the cannabinoid receptors. It has been shown that aerobic exercise causes elevated plasma anandamide levels, where the magnitude of this increase is highest in moderate exercise intensity (ie, exercising at ~ 70-80% maximum heart rate). Increased plasma anandamide levels are associated with psychoactive effects because anandamide is able to cross the blood-brain barrier and act in the central nervous system. Thus, since anandamide is an euphoriant and aerobic exercise associated with the effects of euphoria, it has been proposed that anandamide partially mediates the effects of improving short-term moods of exercise (eg, high runner euphoria) through enhancement induced by synthesis exercise.
In mice it was shown that certain features of the runner were high depending on the cannabinoid receptors. Pharmacological or genetic disorders of cannabinoid signaling via cannabinoid receptors prevent the analgesic effect and decrease anxiety from running.
Neurotransmitter monoamina
Glutamate and GABA
Glutamate, one of the most common neurochemical in the brain, is the excitatory neurotransmitter involved in many aspects of brain functions, including learning and memory. Based on animal models, the sport seems to normalize excessive levels of glutamate neurotransmission in the nucleus accumbens that occurs in drug addiction. A review of the effects of exercise on neurocardiac function in preclinical models noted that neuroplasticity induced by exercise of the rostral ventrolateral medulla (RVLM) has inhibitory effects on neurotransmission glutamatergik in these areas, in turn reducing sympathetic activity; reviews the hypothesis that this neuroplasticity in RVLM is a mechanism by which regular exercise prevents inactivated cardiovascular disease.
Acetylcholine
Effects on children
Sibley and Etnier (2003) conducted a meta-analysis that looked at the relationship between physical activity and cognitive performance in children. They reported favorable relationships in the categories of perceptual skills, intelligence, achievement, verbal tests, math tests, academic and other levels of development/readiness, with the exception of memory, found to be unrelated to physical activity. The strongest correlations for the 4-7 and 11-13 year age range. On the other hand, Chaddock and colleagues (2011) found a contrasting result between Sibley and Etnier meta-analysis. In their research, the hypothesis is that the less fit children will perform poorly in the executive control of memory and have smaller hippocampal volumes compared to the older children. Instead of physical activity unrelated to memory in children between 4 and 18 years, it may be that higher pre-teen fitness has a larger hippocampal volume, than pre-teens low fitness. According to a previous study by Chaddock and colleagues (Chaddock et al. 2010), larger hippocampal volumes will result in better executive control of memory. They conclude that the hippocampal volume is positively related to performance on relational memory tasks. Their findings are the first to show that aerobic fitness may be related to the structure and function of the preteen human brain. In Best's (2010) meta-analysis of the effect of activity on the executive function of children, there are two different experimental designs used to assess aerobic exercise on cognition. The first is a chronic exercise, in which children are randomly assigned to aerobic exercise schedule for several weeks and then assessed at the end. The second is an acute exercise, which examines immediate changes in cognitive function after each session. Their results indicate that aerobic exercise can briefly assist the executive function of children and also affect a more lasting improvement to executive function. Other studies have shown that exercise is not related to academic achievement, probably because of the parameters used to determine what academic achievement is. This field of study has become a focus for education boards that make decisions about whether physical education should be applied in the school curriculum, how much time should be dedicated to physical education, and its impact on other academic subjects.
Another study found that sixth graders who participated in strong physical activity at least three times a week had the highest scores compared to those who participated in moderate or nonexistent physical activity. Children who participated in strong physical activity scored three points higher, on average, on their academic tests, which consisted of math, science, English, and world studies.
Animal studies have also shown that exercise can affect brain development early in life. Mice that have access to wheel runs and other exercise equipment have better neural growth in the nervous system involved in learning and memory. Neuroimaging of the human brain has produced similar results, in which exercise causes changes in the structure and function of the brain. Some studies have linked low levels of aerobic fitness in children with impaired executive function in older adults, but there is mounting evidence that it may also be linked to a lack of selective attention, inhibition of response, and disturbance control.
Effect on central nervous system disorder
Addictions
Clinical and preclinical evidence suggests that consistent aerobic exercise, especially endurance exercises (eg, marathon runs), actually prevents the development of certain drug addictions and is an effective adjunctive to drug addiction, and psychostimulary addiction in particular. Consistent aerobic exercise, highly dependent (ie, based on duration and intensity) reduces the risk of drug addiction, which appears to occur through the reversal of drug-related neuroplasticity, associated with addiction. One review noted that exercise can prevent the development of drug addiction by altering phosphorus or c-Fos immunoreactivity in the striatum or other parts of the reward system. In addition, aerobic exercise reduces the administration of psychostimulant self-administration, reduces recovery (ie, relapsing) of drug-seeking, and adversely affects dopamine striatal receptors D 2 (DRD2) signaling (increase in DRD2 density) to those induced by the use of pathological stimulation (decreased DRD2 density). Consequently, consistent aerobic exercise can lead to better treatment outcomes when used as an adjunct to drug addiction. In 2016, more clinical research is still needed to understand the mechanisms and confirm the effectiveness of exercise in the treatment and prevention of drug addiction.
Attention deficit hyperactivity disorder
Regular physical exercise, especially aerobic exercise, is an effective adjunctive treatment for ADHD in children and adults, especially when combined with stimulant drugs (ie, amphetamine or methylphenidate), although the intensity and type of aerobic exercise is best for improving symptoms not when this is known. In particular, the long-term effects of regular aerobic exercise on ADHD individuals include better behavior and motor skills, improved executive function (including attention, inhibitory control, and planning, among other cognitive domains), faster information processing speeds, and better memory. Parent-teacher ratings of behavioral and socio-emotional outcomes in response to aerobic exercise regularly include: better overall function, reduced ADHD symptoms, better self-esteem, reduced anxiety and depression, fewer somatic complaints, academic behavior and better classes, and better social behavior. Exercising while taking stimulant drugs adds stimulant drug effects to executive function. It is believed that the short-term effects of this exercise are mediated by the increase in synaptic amounts of dopamine and norepinephrine in the brain.
Major depressive disorder
A number of medical reviews indicate that exercise has a real and persistent antidepressant effect in humans, an effect believed to be mediated through an increase in
A 2015 review of clinical evidence that included medical guidelines for the treatment of depression with exercise noted that the available evidence on the therapeutic efficacy of exercise for depression suffers from some limitations; Nonetheless, it states that there is clear evidence of efficacy for reducing symptoms of depression. The review also notes that patient characteristics, types of depressive disorders, and the nature of the exercise program all affect the antidepressant properties of exercise therapy. A meta-analysis from July 2016 concluded that physical exercise improves overall quality of life in individuals with depression relative to control.
Brain cancer
Mild cognitive impairment
The American Academy of Neurology January 2018 updates their clinical practice guidelines for mild cognitive impairment stating that physicians should recommend regular exercise (twice per week) to individuals who have been diagnosed with this condition. This guide is based on a number of high-quality evidence that supports the effectiveness of regular physical exercise (twice weekly for a period of 6 months) to improve cognitive symptoms in individuals with mild cognitive impairment.
Neurodegenerative disorders
Alzheimer's Disease
Alzheimer's Disease is a cortical neurodegenerative disorder and the most common form of dementia, representing approximately 65% ​​of all cases of dementia; it is characterized by impaired cognitive function, behavioral abnormalities, and reduced capacity to perform basic activities of everyday life. Two meta-analytic systematic reviews of randomized controlled trials with a duration of 3-12 months have examined the effects of physical exercise on the characteristics of Alzheimer's disease mentioned earlier. The review found beneficial effects of physical exercise on cognitive function, cognitive impairment rate, and ability to perform daily activities in individuals with Alzheimer's disease. One review suggested that, based on a transgenic mouse model, the cognitive effects of exercise on Alzheimer's disease can result from a reduction in the quantity of amyloid plaque.
The Caerphilly Candidate Study followed 2,375 men over 30 years and examined the relationship between healthy lifestyle and dementia, among other factors. Analysis of Caerphilly study data has found that exercise is associated with a lower incidence of dementia and decreased cognitive impairment. The subsequent systematic review of longitudinal studies also found higher levels of physical activity to be associated with reduced risk of dementia and cognitive decline; the review further confirms that increased physical activity appears to be causally related to this risk reduction.
Parkinson's disease
Parkinson's disease (PD) is a movement disorder that produces symptoms such as bradykinesia, stiffness, shaking, and gait disturbances.
A review by Kramer and colleagues (2006) found that some neurotransmitter systems are influenced by exercise in a positive way. Several studies have reported seeing an increase in brain health and cognitive function due to exercise. One particular study by Kramer and colleagues (1999) found that aerobic training enhanced the executive control process supported by the frontal and prefrontal regions of the brain. These areas are responsible for cognitive deficits in PD patients, but there is speculation that differences in the neurochemical environment in the frontal lobe of PD patients may inhibit the benefits of aerobic exercise. Nocera and colleagues (2010) conducted case studies based on this literature in which they gave the initial PD participants to mid-stage stages, and the cognitive/linguistic control group with exercise regimen. Individuals perform 20 minutes of aerobic exercise three times a week for 8 weeks on a stationary exercise cycle. It was found that aerobic exercise improves several measures of cognitive function, providing evidence that the exercise regimen may benefit patients with PD.
See also
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References
Source of the article : Wikipedia
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