Posts Tagged Aerobic Exercise

[WEB PAGE] Aerobic Exercise Aids Post-Stroke Walking, Endurance Improvements

http://www.dreamstime.com/stock-photography-exercise-concept-wall-poster-image49345202

 

Stroke survivors who completed group-based aerobic exercise programs similar in design and duration to cardiac rehabilitation programs significantly improved their aerobic endurance and walking ability, according to a recent study.

The study was published in Journal of the American Heart Association, the Open Access Journal of the American Heart Association/American Stroke Association.

Stroke remains the leading cause of disability in the US, and physical therapy is often prescribed to improve physical impairments after stroke. Most current rehabilitation care following stroke has little to no focus on aerobic fitness, and when continued rehabilitation activity is suggested patients often fail to keep active without any support or guidance, according to an analysis of 19 published studies to assess the impact of aerobic exercise programs on endurance and walking ability after stroke.

“The physical therapy we currently provide to patients after a stroke focuses more on improving the ability to move and move well rather than on increasing how far and long you can move,” says Elizabeth Regan, DPT, study lead author, and PhD candidate in Exercise Science at the University of South Carolina, in a media release from the American Heart Association.

“It doesn’t matter how well you can walk if your endurance level keeps you at home.”

The study included nearly 500 adults (average ages between 54-71) who completed aerobic exercise programs similar in structure to cardiac rehabilitation. Participants attended two to three sessions per week for about three months. Of nearly two dozen different exercise groups, walking was the most common type of activity, followed by stationary cycling and then mixed mode aerobic exercise. Physical abilities were tested before and after the intervention.

Looking at results by activity type, researchers found:

  • Mixed aerobic activity provides the best result (four treatment groups) followed by walking (12 treatment groups).
  • Cycling or recumbent stepping (machine that allows stepping while in seated position) while still significant was the least effective (seven treatment groups).
  • Overall, participants significantly improved their endurance level and walking speed.
  • On average, participants walked almost half the size of a football field farther during a six-minute walking test. Participants with mild movement impairments benefited the most.

“These benefits were realized regardless of how long it had been since their stroke,” Regan comments, in the release. “Our analysis included stroke survivors across a wide range, from less than six months to greater than a year since their stroke, and the benefits were seen whether they started an aerobic exercise program one month or one year after having a stroke.”

“Cardiac rehab programs may be a viable option for patients after a stroke who have health risks and endurance losses similar to traditional cardiac rehab participants,” states Stacy Fritz, PhD, PT, the study’s co-author and associate professor of exercise science in the Physical Therapy Program at the University of South Carolina.

“Almost every hospital has a cardiac rehab program, so it’s an existing platform that could be used for stroke survivors. Funneling patients with stroke into these existing programs may be an easy, cost-effective solution with long-term benefits.”

While this study suggests group-based aerobic exercise programs improve health and endurance in stroke survivors, no control group analysis was performed for results comparison. Limited follow-up data were available to determine whether the health benefits persisted.

[Source(s): American Heart Association, Science Daily]

 

via Aerobic Exercise Aids Post-Stroke Walking, Endurance Improvements – Rehab Managment

, , ,

Leave a comment

[Abstract] Forced, Not Voluntary, Aerobic Exercise Enhances Motor Recovery in Persons With Chronic Stroke

Background. The recovery of motor function following stroke is largely dependent on motor learning–related neuroplasticity. It has been hypothesized that intensive aerobic exercise (AE) training as an antecedent to motor task practice may prime the central nervous system to optimize motor recovery poststroke.

Objective. The objective of this study was to determine the differential effects of forced or voluntary AE combined with upper-extremity repetitive task practice (RTP) on the recovery of motor function in adults with stroke.

Methods. A combined analysis of 2 preliminary randomized clinical trials was conducted in which participants (n = 40) were randomized into 1 of 3 groups: (1) forced exercise and RTP (FE+RTP), (2) voluntary exercise and RTP (VE+RTP), or (3) time-matched stroke-related education and RTP (Edu+RTP). Participants completed 24 training sessions over 8 weeks.

Results. A significant interaction effect was found indicating that improvements in the Fugl-Meyer Assessment (FMA) were greatest for the FE+RTP group (P = .001). All 3 groups improved significantly on the FMA by a mean of 11, 6, and 9 points for the FE+RTP, VE+RTP, and Edu+RTP groups, respectively. No evidence of a treatment-by-time interaction was observed for Wolf Motor Function Test outcomes; however, those in the FE+RTP group did exhibit significant improvement on the total, gross motor, and fine-motor performance times (P ≤ .01 for all observations).

Conclusions. Results indicate that FE administered prior to RTP enhanced motor skill acquisition greater than VE or stroke-related education. AE, FE in particular, should be considered as an effective antecedent to enhance motor recovery poststroke.

via Forced, Not Voluntary, Aerobic Exercise Enhances Motor Recovery in Persons With Chronic Stroke – Susan M. Linder, Anson B. Rosenfeldt, Sara Davidson, Nicole Zimmerman, Amanda Penko, John Lee, Cynthia Clark, Jay L. Alberts, 2019

, , , , , , , , , ,

Leave a comment

[Abstract] Forced, Not Voluntary, Aerobic Exercise Enhances Motor Recovery in Persons With Chronic Stroke

Background. The recovery of motor function following stroke is largely dependent on motor learning–related neuroplasticity. It has been hypothesized that intensive aerobic exercise (AE) training as an antecedent to motor task practice may prime the central nervous system to optimize motor recovery poststroke.

Objective. The objective of this study was to determine the differential effects of forced or voluntary AE combined with upper-extremity repetitive task practice (RTP) on the recovery of motor function in adults with stroke.

Methods. A combined analysis of 2 preliminary randomized clinical trials was conducted in which participants (n = 40) were randomized into 1 of 3 groups: (1) forced exercise and RTP (FE+RTP), (2) voluntary exercise and RTP (VE+RTP), or (3) time-matched stroke-related education and RTP (Edu+RTP). Participants completed 24 training sessions over 8 weeks.

Results. A significant interaction effect was found indicating that improvements in the Fugl-Meyer Assessment (FMA) were greatest for the FE+RTP group (P = .001). All 3 groups improved significantly on the FMA by a mean of 11, 6, and 9 points for the FE+RTP, VE+RTP, and Edu+RTP groups, respectively. No evidence of a treatment-by-time interaction was observed for Wolf Motor Function Test outcomes; however, those in the FE+RTP group did exhibit significant improvement on the total, gross motor, and fine-motor performance times (P ≤ .01 for all observations).

Conclusions. Results indicate that FE administered prior to RTP enhanced motor skill acquisition greater than VE or stroke-related education. AE, FE in particular, should be considered as an effective antecedent to enhance motor recovery poststroke.

via Forced, Not Voluntary, Aerobic Exercise Enhances Motor Recovery in Persons With Chronic Stroke – Susan M. Linder, Anson B. Rosenfeldt, Sara Davidson, Nicole Zimmerman, Amanda Penko, John Lee, Cynthia Clark, Jay L. Alberts,

, , , , , ,

Leave a comment

[Abstract] Physiological Responses and Perceived Exertion During Robot-Assisted and Body Weight–Supported Gait After Stroke

Introduction. Physiological responses are rarely considered during walking after stroke and if considered, only during a short period (3-6 minutes). The aims of this study were to examine physiological responses during 30-minute robot-assisted and body weight–supported treadmill and overground walking and compare intensities with exercise guidelines.

Methods. A total of 14 ambulatory stroke survivors (age: 61 ± 9 years; time after stroke: 2.8 ± 2.8 months) participated in 3 separate randomized walking trials. Patients walked overground, on a treadmill, and in the Lokomat (60% robotic guidance) for 30 minutes at matched speeds (2.0 ± 0.5 km/h) and matched levels of body weight support (BWS; 41% ± 16%). Breath-by-breath gas analysis, heart rate, and perceived exertion were assessed continuously.

Results. Net oxygen consumption, net carbon dioxide production, net heart rate, and net minute ventilation were about half as high during robot-assisted gait as during body weight–supported treadmill and overground walking (P < .05). Net minute ventilation, net breathing frequency, and net perceived exertion significantly increased between 6 and 30 minutes (respectively, 1.8 L/min, 2 breaths/min, and 3.8 units). During Lokomat walking, exercise intensity was significantly below exercise recommendations; during body weight–supported overground and treadmill walking, minimum thresholds were reached (except for percentage of heart rate reserve during treadmill walking).

Conclusion. In ambulatory stroke survivors, the oxygen and cardiorespiratory demand during robot-assisted gait at constant workload are considerably lower than during overground and treadmill walking at matched speeds and levels of body weight support. Future studies should examine how robotic devices can be Future studies should examine how robotic devices can be exploited to induce aerobic exercise.

 

via Physiological Responses and Perceived Exertion During Robot-Assisted and Body Weight–Supported Gait After Stroke – Nina Lefeber, Emma De Keersmaecker, Stieven Henderix, Marc Michielsen, Eric Kerckhofs, Eva Swinnen, 2018

, , , , , , ,

Leave a comment

[Abstract] A randomized controlled trial of a walking training with simultaneous cognitive demand (dual‐task) in chronic stroke

Abstract

Background and purpose

The aim was to evaluate the tolerability of, adherence to and efficacy of a community walking training programme with simultaneous cognitive demand (dual‐task) compared to a control walking training programme without cognitive distraction.

Methods

Adult stroke survivors at least 6 months after stroke with a visibly obvious gait abnormality or reduced 2‐min walk distance were included in a two‐arm parallel randomized controlled trial of complex intervention with blinded assessments. Participants received a 10 week, bi‐weekly, 30 min treadmill programme at an aerobic training intensity (55%–85% heart rate maximum), either with or without simultaneous cognitive demands. Outcome was measured at 0, 11 and 22 weeks. The primary assessment involved 2‐min walk tests with and without cognitive distraction to investigate the dual‐task effect on walking and cognition; secondary results were the Short Form Health Survey 36, EuroQol‐5D‐5L, the Physical Activity Scale for the Elderly (PASE) and step activity.

Results

Fifty stroke patients were included; 43 received allocated training and 45 completed all assessments. The experimental group (n = 26) increased their mean (SD) 2‐min walking distance from 90.7 (8.2) to 103.5 (8.2) m, compared with 86.7 (8.5) to 92.8 (8.6) m in the control group, and their PASE score from 74.3 (9.1) to 89.9 (9.4), compared with 94.7 (9.4) to 77.3 (9.9) in the control group. Statistically, only the change in the PASE differed between the groups (P = 0.029), with the dual‐task group improving more. There were no differences in other measures.

Conclusions

Walking with specific additional cognitive distraction (dual‐task training) might increase activity more over 12 weeks, but the data are not conclusive.

 

via A randomized controlled trial of a walking training with simultaneous cognitive demand (dual‐task) in chronic stroke – Meester – – European Journal of Neurology – Wiley Online Library

, , , , , , ,

Leave a comment

[Abstract] Aerobic Training in Canadian Stroke Rehabilitation Programs

Background and Purpose: Aerobic training (AT) is recommended for people after stroke, yet uptake and operationalization of AT in clinical practice in Canada have not been measured. We surveyed inclusion of structured AT and barriers to implementation in public inpatient/outpatient stroke rehabilitation programs across Canada.

Methods: A Web-based questionnaire was sent to 89 stroke rehabilitation program leads.

Results: Forty-six programs from 7 of 9 eligible Canadian provinces/territories completed the questionnaire. Seventy-eight percent of programs reported including AT, with most (75%) excluding participants with severe physical impairments, and 28% excluding those with coexisting cardiac conditions. A greater proportion of dedicated stroke rehabilitation programs prescribed AT, compared to nondedicated stroke units (68.8% vs 31.3%, P = 0.02). The top 2 challenges for programs that included and did not include AT were “insufficient time within therapy sessions” and “length of stay in rehabilitation.” Programs that did not include AT ranked “not a goal of most patients” and “not an organizational/program priority” as third and fourth, whereas they were ranked eighth and thirteenth by programs with AT. Best practice recommendations were inconsistently followed for conducting preparticipation exercise testing (36.1%) and for monitoring patients from higher-risk populations, specifically people with diabetes at risk for hypoglycemia (78.8%) and hypertension (36.6%). Of programs conducting preparticipation exercise testing, 91% did not monitor electrocardiography.

Discussion and Conclusions: Most stroke rehabilitation programs across Canada include AT. People with severe physical impairment and those with cardiac, metabolic, and hemodynamic comorbidities may be excluded or not appropriately monitored during exercise. More detailed guidelines and training practices are needed to address these challenges.

Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A233).

via Aerobic Training in Canadian Stroke Rehabilitation Programs : Journal of Neurologic Physical Therapy

, , , , , , , , ,

Leave a comment

[ARTICLE] AExaCTT – Aerobic Exercise and Consecutive Task-specific Training for the upper limb after stroke: Protocol for a randomised controlled pilot study – Full Text

Abstract

Motor function may be enhanced if aerobic exercise is paired with motor training. One potential mechanism is that aerobic exercise increases levels of brain-derived neurotrophic factor (BDNF), which is important in neuroplasticity and involved in motor learning and motor memory consolidation. This study will examine the feasibility of a parallel-group assessor-blinded randomised controlled trial investigating whether task-specific training preceded by aerobic exercise improves upper limb function more than task-specific training alone, and determine the effect size of changes in primary outcome measures. People with upper limb motor dysfunction after stroke will be allocated to either task-specific training or aerobic exercise and consecutive task-specific training. Both groups will perform 60 hours of task-specific training over 10 weeks, comprised of 3 × 1 hour sessions per week with a therapist and 3 × 1 hours of home-based self-practice per week. The combined intervention group will also perform 30 minutes of aerobic exercise (70–85%HRmax) immediately prior to the 1 hour of task-specific training with the therapist. Recruitment, adherence, retention, participant acceptability, and adverse events will be recorded. Clinical outcome measures will be performed pre-randomisation at baseline, at completion of the training program, and at 1 and 6 months follow-up. Primary clinical outcome measures will be the Action Research Arm Test (ARAT) and the Wolf Motor Function Test (WMFT). If aerobic exercise prior to task-specific training is acceptable, and a future phase 3 randomised controlled trial seems feasible, it should be pursued to determine the efficacy of this combined intervention for people after stroke.

1. Introduction

1.1. Background

Currently 440,000 persons after stroke live in community settings in Australia [1]. Many with stroke experience chronic disability and although two-thirds receive care each day [1], the majority still have unmet needs [2]. Upper limb dysfunction is a persistent and disabling problem present in 69% of persons after stroke in Australia [3]. Upper limb dysfunction is a major contributor to poor well-being and quality-of-life [4]; [5]; [6] ;  [7]. Unsurprisingly, advancing treatments for upper limb recovery is a top ten research priority for persons after stroke and their carers [8].

In Australia, 87% of persons with stroke-attributable upper limb impairments receive task-specific training [3]. Task-specific training is a progressive training strategy that utilises practice of goal-directed, real-world, context-specific tasks that are intrinsically and/or extrinsically meaningful to the person, to enable them to undertake activities of daily living [9] and may improve upper limb motor function after stroke [9]; [10] ;  [11].

Improvements in motor function coincide with structural and functional reorganisation of the brain [12]; [13]; [14] ;  [15]. The brain’s ability to undergo these changes is denoted as neuroplasticity. Capitalisation and enhancement of neuroplasticity in peri-infarct and non-primary motor regions may promote recovery via an increased response to motor training and other neurorehabilitative interventions [16]; [17] ;  [18].

Many studies show that aerobic exercise (prolonged, rhythmical activity using large muscle groups to increase heart rate) enhances neuroplasticity [19], grey matter volume, white matter integrity [20]; [21] ;  [22] and brain activation [23]; [24] ;  [25]. Furthermore increasing evidence indicates that lower limb aerobic exercise increases upper limb motor function. A single bout of aerobic cycling exercise can improve long-term retention of a motor skill in healthy individuals [26], regardless of whether performed immediately before or after motor training [27].

Aerobic exercise increases BDNF [28]. Improvements in motor skill learning and memory induced by aerobic exercise have been associated with increased peripheral blood concentrations of BDNF [26]. BDNF is involved with neurogenesis [29] and neuroprotection [30] in the human brain [31], thereby playing an important role in stroke recovery, including facilitating functional upper limb motor rehabilitation [32].

In chronic stroke, an 8-week programme of lower extremity endurance cycling enhanced upper extremity fine motor control [33]. Also, a single bout of aerobic treadmill exercise improved grasp function of the hemiparetic hand [34]. As aerobic exercise alone can enhance motor function after stroke, motor learning in stroke rehabilitation may be facilitated if aerobic exercise is paired with motor training [35] ;  [36].

1.2. Aims and objectives

The aims of this study are to 1) assess the feasibility of conducting a randomised controlled trial to compare the effects of task-specific training preceded by aerobic exercise to task-specific training alone on upper limb motor function after stroke; and 2) calculate the effect size of changes in primary clinical outcome measures to evaluate proof-of-concept and inform calculation of sample size for a future phase III trial. This includes investigating potential neural correlates of exercise-induced motor function changes using peripheral blood serum BDNF measurement and multi-modal MRI.

2. Methods

2.1. Study design

This is a parallel-group assessor-blinded randomised controlled pilot study (Fig. 1). One group will undertake task-specific training alone and the other group will undertake 30 minutes of aerobic cycling exercise prior to their task-specific training. The interventions will be delivered by a therapist 3 days per week for 10 weeks. Both groups will be provided with an individually-prescribed task-specific training programme to practice at home for 60 minutes, 3 times per week. Assessments will be conducted at baseline, within 1 week from the end of intervention, and 1 and 6 months following the end of the intervention period. Ethics approval has been obtained from the Hunter New England Human Research Ethics Committee (14/12/10/4.07) and registered with the University of Newcastle Human Research Ethics Committee (H-2015-0105). The study is registered with the Australian and New Zealand Clinical Trials Registry (ACTRN12616000848404).

Continue —>  AExaCTT – Aerobic Exercise and Consecutive Task-specific Training for the upper limb after stroke: Protocol for a randomised controlled pilot study

, , , , , , , ,

Leave a comment

[WEB PAGE] Can A Single Exercise Session Benefit Your Brain? – Neuroscience News

Summary: Researchers document not only the behavioral and cognitive effects of a single exercise session, but also the neurochemical and neurophysiological changes that occur.

Source: IOS Press.

Even a single bout of physical activity can have significant positive effects on people’s mood and cognitive functions, according to a new study inBrain Plasticity.

In a new review of the effects of acute exercise published in Brain Plasticity, researchers not only summarize the behavioral and cognitive effects of a single bout of exercise, but also summarize data from a large number of neurophysiological and neurochemical studies in both humans and animals showing the wide range of brain changes that result from a single session of physical exercise (i.e., acute exercise).

There is currently enormous interest in the beneficial effects of aerobic exercise on a wide range of brain functions including mood, memory, attention, motor/reaction times, and even creativity. Understanding the immediate effects of a single bout of exercise is the first step to understanding how the positive effects of exercise may accrue over time to cause long-lasting changes in select brain circuits.

According to principal investigator Wendy A. Suzuki, PhD, Professor of Neural Science and Psychology in the Center for Neural Science, New York University, “Exercise interventions are currently being used to help address everything from cognitive impairments in normal aging, minimal cognitive impairment (MCI), and Alzheimer’s disease to motor deficits in Parkinson’s disease and mood states in depression. Our review highlights the neural mechanisms and pathways by which exercise might produce these clinically relevant effects.”

The investigators summarized a large and growing body of research examining the changes that occur at the cognitive/behavioral, neurophysiological, and neurochemical levels after a single bout of physical exercise in both humans and animals. They reviewed brain imaging and electrophysiological studies, including electroencephalography (EEG), functional magnetic resonance imaging (fMRI), functional near-infrared spectroscopy (fNIRS), and transcranial magnetic stimulation (TMS). They then turned to neurochemical studies, including lactate, glutamate and glutamine metabolism, effects on the hypothalamic-pituitary-adrenal (HPA) axis through cortisol secretion, and neurotrophins such as brain-derived neurotrophic factor (BDNF), insulin-like growth factor 1 (IGF-1), and vascular endothelial growth factor (VEGF). Neurotransmitter studies of monoamines (dopamine, serotonin, epinephrine and norepinephrine), acetylcholine, glutamate and gamma-aminobutyric acid (GABA) were reviewed, as well as neuromodulators such as endogenous opioids and endocannabinoids.

Image shows a mouse on a wheel and a woman running a race.

What is the relationship between the central neurochemical changes following acute exercise that have mainly been described in rodents and the behavioral changes seen after acute exercise that have mainly been described in humans? NeuroscienceNews.com image is credited to Henriette van Praag and MarathonFoto.

This extensive review resulted in three main observations. First, the most consistent behavioral effects of acute exercise are improved executive function, enhanced mood, and decreased stress levels. Second, neurophysiological and neurochemical changes that have been reported after acute exercise show that widespread brain areas and brain systems are activated. Third, one of the biggest open questions in this area is the relationship between the central neurochemical changes following acute exercise, that have mainly been described in rodents, and the behavioral changes seen after acute exercise reported in humans. Bridging this gap will be an important area of future study.

Co-author Julia C. Basso, PhD, post-doctoral research fellow, Center for Neural Science at New York University, commented, “The studies presented in this review clearly demonstrate that acute exercise has profound effects on brain chemistry and physiology, which has important implications for cognitive enhancements in healthy populations and symptom remediation in clinical populations.”

ABOUT THIS NEUROSCIENCE RESEARCH ARTICLE

Source: Diana Murray – IOS Press
Image Source: NeuroscienceNews.com image is credited to Henriette van Praag and MarathonFoto.
Original Research: Full open access research for “The Effects of Acute Exercise on Mood, Cognition, Neurophysiology, and Neurochemical Pathways: A Review” by Basso, Julia C. and Suzuki, Wendy A. in Brain Plasticity. Published online March 28 2017 doi:10.3233/BPL-160040

Source: Can A Single Exercise Session Benefit Your Brain? – Neuroscience News

, ,

Leave a comment

[WEB SITE] How Do Neuroplasticity and Neurogenesis Rewire Your Brain? – Psychology Today

Source: XStudio3D/Shutterstock

For over a decade, neuroscientists have been trying to figure out how neurogenesis (the birth of new neurons) and neuroplasticity (the malleability of neural circuits) work together to reshape how we think, remember, and behave.

This week, an eye-opening new study, “Adult-Born Neurons Modify Excitatory Synaptic Transmission to Existing Neurons” reported how newborn neurons (created via neurogenesis) weave themselves into a “new and improved” neural tapestry. The January 2017 findings were published in the journal eLife.

During this state-of-the-art study on mice, neuroscientists at the University of Alabama at Birmingham (UAB) found that the combination of neurogenesis and neuroplasticity caused less-fit older neurons to fade into oblivion and die off as the sprightly, young newborn neurons took over existing neural circuits by making more robust synaptic connections.

For their latest UAB study, Linda Overstreet-Wadiche and Jacques Wadiche—who are both associate professors in the University of Alabama at Birmingham Department of Neurobiology—focused on neurogenesis in the dentate gyrus region of the hippocampus.

The dentate gyrus is an epicenter of neurogenesis responsible for the formation of new episodic memories and the spontaneous exploration of novel environments, among other functions.

More specifically, the researchers focused on newly born granule cell neurons in the dentate gyrus that must become wired into a neural network by forming synapses via neuroplasticity in order to stay alive and participate in ongoing neural circuit function.

There are only two major brain regions that are currently believed to have the ability to continually give birth to new neurons via neurogenesis in adults; one is the hippocampus (long-term and spatial memory hub) the second is the cerebellum (coordination and muscle memory hub). Notably, granule cells have the highest rate of neurogenesis. Both the hippocampus and cerebellum are packed, chock-full with granule cells.

Interestingly, moderate to vigorous physical activity (MVPA) is one of the most effective ways to stimulate neurogenesis and the birth of new granule cells in the hippocampus and the cerebellum. (As a cornerstone of The Athlete’s Way platform, I’ve been writing about the link between MVPA and neurogenesis for over a decade. To read a wide range of Psychology Today blog posts on the topic click on this link.)

Drawing of Purkinje cells (A) and granule cells (B) from pigeon cerebellum by Santiago Ramón y Cajal, 1899. Source: Instituto Santiago Ramón y Cajal, Madrid, Spain

Granule cells were first identified by Santiago Ramón y Cajal, who made beautiful sketches in 1899 that illustrate how granule cells create synaptic connections with Purkinje cells in the cerebellum. His breathtaking and Nobel Prize-winning illustrations are currently on a museum tour across the United States (on loan from the Instituto Santiago Ramón y Cajal in Madrid, Spain) as part of “The Beautiful Brain” traveling art exhibit.

(As a side note, the olfactory bulb is the only other subcortical brain area known to have high rates of neurogenesis. Speculatively, this could be one reason that scent plays such an indelible and ever-changing role in our memory formation and ‘remembrance of things past.’)

Neurogenesis and Neuroplasticity Work Together to Rewire Neural Circuitry

One of the key aspects of neural plasticity is called Neural Darwinism, or “neural pruning,” which means that any neuron that isn’t ‘fired-and-wired’ together into a network is likely to be extinguished. The latest UAB research suggests that newborn neurons play a role in expediting this process by “winning out” in a survival of the fittest type of neuronal battle against their more elderly or worn out counterparts.

Long before there were neuroscientific studies on neuroplasticity and neurogenesis, Henry David Thoreau unwittingly described the process of how the paths that one’s mind travels can become hardwired (when you get stuck in a rut) by describing a well-worn path through the woods. In Walden, Thoreau writes,

“The surface of the earth is soft and impressible by the feet of men; and so with the paths which the mind travels. How worn and dusty, then, must be the highways of the world, how deep the ruts of tradition and conformity!”

From a psychological standpoint, the latest UAB discovery presents the exciting possibility that when adult-born neurons weave into existing neural networks that new memories are created and older memories may be modified.

Through neurogenesis and neuroplasticity, it may be possible to carve out a fresh and unworn path for your thoughts to travel upon. One could speculate that this process opens up the possibility to reinvent yourself and move away from the status quo or to overcome past traumatic events that evoke anxiety and stress. Hardwired fear-based memories often lead to avoidance behaviors that can hold you back from living your life to the fullest.

Future Research on Neurogenesis Could Lead to New PTSD Treatments

Granule cells in the dentate gyrus are part of a neural circuit that processes sensory and spatial input from other areas of the brain. By integrating sensory and spatial information, the dentate gyrus has the ability to generate unique and detailed memories of an experience.

Before this study, Overstreet-Wadiche and her UAB colleagues had a few basic questions about how the newly born granule cells in the dentate gyrus function. They asked themselves two specific questions:

  1. Since the number of neurons in the dentate gyrus increases by neurogenesis while the number of neurons in the cortex remains the same, does the brain create additional synapses from the cortical neurons to the new granule cells?
  2. Or do some cortical neurons transfer their connections from mature granule cells to the new granule cells?

Through a series of complex experiments with mice, Overstreet-Wadiche et al. found that some of the cortical neurons in the cerebral cortex transferred all of their former connections with older granule cells (that may have been worn out or past their prime) to the freshly born granule cells that were raring to go.

This revolutionary discovery opens the door to examine how the redistribution of synapses between old and new neurons helps the dentate gyrus stay up to date by forming new connections.

One of the key questions the researchers want to dive deeper into during upcoming experiments is: “How does this redistribution relate to the beneficial effects of exercise, which is a natural way to increase neurogenesis?”

In the future, it’s possible that cutting-edge research on neurogenesis and neuroplasticity could lead to finely-tuned neurobiological treatments for ailments such as post-traumatic stress disorder (PTSD) and dementia. In a statement to UAB, Overstreet-Wadiche said,

“Over the last 10 years there has been evidence supporting a redistribution of synapses between old and new neurons, possibly by a competitive process that the new cells tend to ‘win.’ Our findings are important because they directly demonstrate that, in order for new cells to win connections, the old cells lose connections.

So, the process of adult neurogenesis not only adds new cells to the network, it promotes plasticity of the existing network. It will be interesting to explore how neurogenesis-induced plasticity contributes to the function of this brain region.

Neurogenesis is typically associated with improved acquisition of new information, but some studies have also suggested that neurogenesis promotes ‘forgetting’ of existing memories.”

Aerobic Exercise Is the Most Effective Way to Stimulate Neurogenesis and Create Adult-Born Neurons

For the past 10 years, the actionable advice I’ve given in The Athlete’s Way has been rooted in the belief that through the daily process of working out anyone can stimulate neurogenesis and optimize his or her mindset and outlook on life via neuroplasticity.

“The Athlete’s Way” program is designed to reshape neural networks and optimize your mindset. Since the beginning, this program has been based on the discovery that aerobic activity produces brain-derived neurotrophic factor (BDNF) and stimulates the birth of new neurons through neurogenesis. I describe my philosophy in the Introduction to The Athlete’s Way,

“Shifting the focus from thinner thighs to stronger minds makes this exercise book unique. The Athlete’s Way does not focus just on sculpting six-pack abs or molding buns of steel. We are more interested in bulking up your neurons and reshaping your synapses to create an optimistic, resilient, and determined mindset. The goal is transformation from the inside out.

My mission is to get this message to you so that you can use neurobiology and behavioral models to help improve your life through exercise. I am a zealot about the power of sweat to transform people’s lives by transforming their minds. My conviction is strong and authentic because I have lived it.”

I created The Athlete’s Way along with the indispensable help of my late father, Richard Bergland, who was a visionary neuroscientist, neurosurgeon, and author of The Fabric of Mind (Viking).

A decade ago, when I published The Athlete’s Way: Sweat and the Biology of Bliss (St. Martin’s Press) I put neurogenesis and neuroplasticity in the spotlight. At the time, the discovery of neurogenesis was brand new, and still a radical notion in mainstream neuroscience.

In the early 21st century, most experts still believed that human beings were born with all the neurons they would have for their entire lifespan. If anything, it was believed that people could only lose neurons or “kill brain cells” as we got older.

Understandably, when I published The Athlete’s Way in 2007 there were lots of skeptics and naysayers who thought my ideas about reshaping mindset using a combination of neurogenesis and neuroplasticity through moderate to vigorous physical activity were ludicrous.

For the past 10 years, I’ve kept my antennae up and my finger on the pulse of all the latest research on neurogenesis and neuroplasticity hoping to find additional empirical evidence that gives more scientific credibility to my system of belief and The Athlete’s Way methodology.

Needless to say, I was over the moon and ecstatic this morning when I read about the new research by Linda Overstreet-Wadiche and Jacques Wadiche that pinpoints the specifics of how adult-born neurons modify existing neural circuits. This is fascinating stuff!

These are exciting times in neuroscience. Modern day neuroscientific techniques are poised to solve many more riddles regarding the complex mechanism by which neurogenesis and neuroplasticity work together as a dynamic duo to reshape our neural networks and functional connectivity between brain regions. Stay tuned for future empirical evidence and scientific research on neurogenesis and neuroplasticity in the months and years ahead.

In the meantime, if you’d like to read a free excerpt from The Athlete’s Way that provides some simple actionable advice and practical ways for you to stimulate neurogenesis and rewire your brain via neuroplasticity and moderate to vigorous physical activity—check out these pages from a section of my book titled: Neuroplasticity and Neurogenesis: Combining Neuroscience and Sport.”

References

Elena W Adlaf, Ryan J Vaden, Anastasia J Niver, Allison F Manuel, Vincent C Onyilo, Matheus T Araujo, Cristina V Dieni, Hai T Vo, Gwendalyn D King, Jacques I Wadiche, Linda Overstreet-Wadiche. Adult-born neurons modify excitatory synaptic transmission to existing neurons. eLife, 2017; 6 DOI: 10.7554/eLife.19886

Source: How Do Neuroplasticity and Neurogenesis Rewire Your Brain? | Psychology Today

, , , , ,

Leave a comment

[BLOG POST] How aerobic exercise enhances neuroplasticity in the brain

New research published in the journal Experimental Brain Research suggests a single bout of moderate intensity aerobic exercise enhances neuroplasticity in the brain through its effects on the neurotransmitter GABA.

PsyPost interviewed the study’s corresponding authors, Winston D. Byblow and Ronan A. Mooney of the University of Auckland. Read their responses below:

PsyPost: Why were you interested in this topic?

Habitual exercise appears to be beneficial for health and well-being. It is becoming increasingly evident that acute and chronic participation in aerobic exercise exerts a number of positive effects on the brain such as improved memory and executive function. The underlying mechanisms of exercise-related changes in brain function are not completely understood.

What should the average person take away from your study?

A brief but intense period of aerobic exercise immediately reduces GABA, the main inhibitory neurotransmitter in the brain. GABA play an important role in regulating the brain’s capacity to undergo change or neuroplasticity. We observed reduced excitability of GABA-mediated networks in the motor cortex, which may explain findings from previous studies where enhanced neuroplasticity is observed after aerobic exercise.

Our findings may have implications for individuals after stroke, where GABA is a promising target for promoting neuroplasticity to promote recovery of motor function.

Are there any major caveats? What questions still need to be addressed?

A key limitation of our study was the small sample size of young healthy people. Future studies might examine similar mechanisms in older adults and in people after stroke. We used a stationary bicycle to permit moderate exercise intensity, tailored to the aerobic fitness levels of each participant. Further studies should explore the influence of other exercise modalities and intensities as this would help determine the boundaries for producing the effects which may enhance neuroplasticity. Admittedly, older or clinical populations may struggle with certain exercise intensities/modalities due to functional limitations.

In addition to Byblow and Mooney, the study “Acute aerobic exercise modulates primary motor cortex inhibition” was also co-authored by James P. Coxon, John Cirillo, Helen Glenny and Nicholas Gant.

Source: How aerobic exercise enhances neuroplasticity in the brain

,

Leave a comment

%d bloggers like this: