Can exercising the body improve the health of the mind?


Table of Contents

A Brief History

Kramer, A. F., Erickson K. I., & Colcombe S. J. (2006). Exercise, cognition, and the aging brain. J Appl Physiol, 101, 1237–1242. DOI: 10.1152/japplphysiol.000500.2006.

Kramer, A. F. & Erickson, K. I. (2012). Capitalizing on cortical plasticity: influence of physical activity on cognition and brain function. Trends Cogn Sci, 11(8), 342-8. doi:10.1016/j.tics.2007.06.009.

“It is exercise alone that supports the spirits, and keeps the mind in vigor” Cicero ~65BC

The second president of the United States was quoted, “Exercise invigorates, and enlivens all the faculties of body and of mind…” (Kramer, 2006). Through providing an up-to-date review of published scientific literature we want to investigate the claim that exercise has positive benefits for cognition. Most research in this field that has been conducted through analyses of numerous epidemiological, clinical trials. The absence of disease by primary prevention or the delay of disease progression by means of secondary prevention; also the preservation of executive cognitive function is one way to define a “healthy mind” (Kramer 2012).

Epidemiological review

Over the past decade studies conducted using a self-report method demonstrated there is an inverse correlation between physical activity and age-related cognitive decline and the prevention of neurological disease. One study from an exercise intervention conducted a post assessment (6.2 years) test where 158 individuals out of 1740 men and women over the age of 65 developed Alzheimer’s dementia. Post adjustment of cofounding variables such as education level demonstrated that, “incidence rate for Alzheimer’s disease was significantly higher for individuals that exercised less than three times per week 19.7 per 1,000 person year) compared with those who exercised more than three times per week (13.0 per 1,000 person year)” (Kramer & Erickson, 2012). These results suggest a form of dose-response relationship. Numerous scientific literatures that have been published to similarly support this claim. There is also literature that claims an inverse relationship between physical activity levels and age related cognitive decline. Although there may be substantial evidence supporting the relationship between physical activity and later cognitive function including the absence or delayed progression of neurological disease. There is some inconsistent findings observed that could potentially have risen from the use of self-report measures or the lack of operational and conceptual definitions of physical activity (type, duration and intensity) (Kramer et al., 2006).

Clinical trial review

For approximately four decades, Colcombe and Kramer have conducted meta-analyses on published scientific literature that examined the exercise effects on cognitive function of healthy older adults (Kramer & Erickson, 2012). Studies that qualified must utilize: randomized design for treatment group and controls. The results demonstrated a moderate effect size (0.48) between physical activity and cognition. The largest positive effect was found in executive cognitive functions such as, “planning, scheduling, working memory, inhibitory processes, and multitasking” (Kramer & Erickson, 2012). More importantly these effects were larger when aerobic exercise was combined with strength and flexibility training. It is argued that even a small effect size is beneficial due to the complexity that is the dualist problem (Kramer et al., 2006).

How do we conceptualize the health of the mind?

Vandenbos, R. (2009) APA Concise dictionary of psychology. Washington. American Psychology Association.

World Health Organization. (2006). Constitution of the World Health Organization. Retrieved from http://apps.who.int/gb/bd/PDF/bd47/EN/constitution-en.pdf.

Kim, Y. S., Park, Y. S., Allegrante, J. P., Marks, R., Ok H., Cho, K. O., & Garber, C. E. (2012). Relationship between physical activity and general mental health. Prev Med, 55, 458–463. DOI: 10.1016/j.ypmed.2012.08.021.

Eime, R. M., Young, J., Harvey, J. T., Charity, M. J., & Payne, W. R. (2013). A systematic review of the psychological and social benefits of participation in sport for children and adolescents: informing development of a conceptual model of health through sport. Int J Behav Nutr Phys Act, 10,135. DOI: 10.1186/1479-5868-10-98.

In order for us to conceptualize the health of the mind we must define health. The World Health Organization’s definition of health states: “a state of complete physical, mental, social well-being and not merely the absence of disease and infirmity” (WHO, 2006). With that in “mind”, through the American Psychology Association’s concise definition of mental states that the mental is the mind or its processes including thinking, feeling and related executive processes (Vandenbos, 2009). We now return to classify the health of the mind as some studies states: “directly or indirectly related to the mental health components of the World Health Organization such that it promotes well-being, prevention of mental disorders and, to provide treatment or rehabilitation for those who exhibit mental disorders” (Eime et al., 2013). Furthermore, the mental health components of the WHO defines wellbeing as realizing ones potential, their ability to manage normal life stresses, make positively contribute to their environment (WHO, 2006). One may make the claim that, “Psychological distress is a term that refers to the emotional state, somatic symptoms, discomforts, and impaired coping associated with mental and physical health disorders” Kessler et al. (2002) viewed this as an indicator of general mental health (Kim et al., 2012).

Cognitive aspects of the healthy mind

Capitalizing on cortical plasticity: influence of physical activity on cognition and brain function. Trends Cogn Sci, 11(8), 342-8. doi:10.1016/j.tics.2007.06.009.

This article systematically analyzed three independent literatures that examined the relationship between physical activity and exercise on cognition, brain function and structure. It puts claim that habitual levels of physical activity can maintain and improve cognition and brain function (Kramer & Erickson, 2012).

Age related decline

Nazimek, J. (2009). Active body, healthy mind. The Psychologist, 22(3), 206-209.

Executive cognitive function such as: memory, visuospatial ability, planning, scheduling and working memory tend to decline with age. It is alleged that regular exercise in older adults perform better in cognitive tasks than their sedentary counter parts, especially those who find enjoyment in high levels of physical activity. As a result, this leads to maintained cognitive function and an overall improved quality of life. Some mechanisms for this phenomenon are neurogenesis, brain plasticity and other possible molecular and cellular mechanism will be explored in a bit more detail later (Nazimek, 2009). Furthermore, other mechanisms not explored in depth are related to:

  • Inflammation - inflammation that is present is associated with dementia related cognitive impairment. A study showed that post three week exercise intervention lab mice regained normal cognitive function and spatial memory with voluntary running (Nazimek, 2009).
  • Increase in cytokines - Cytokines are chemical signals, studies show that increased levels of brain cytokines can protect neurons in the hippocampus and may improve cellular communication (Nazimek, 2009).
  • Increased blood flow to the brain is one the most plausible mechanisms. Exercise causes vasodilation in critical regions in the body. This increase in blood flow causes an increase in concentration of oxygen and glucose, which are vital nutrients for the body. Furthermore, the increase in blood flow also results in increase pressure, causing dilation then contraction of cerebral muscles. This acts like a physiological cerebral “massage” (Nazimek, 2009).
  • Exercise may also decrease the risk for cerebrovascular disease such as stroke caused by hypertension. Furthermore, a blockage from stroke could cause increase the risk of oxidative stress (Nazimek, 2009).

Cortical Plasticity

Kramer, A. F., & Erickson, K. I. (2012). Capitalizing on cortical plasticity: influence of physical activity on cognition and brain function. Trends Cogn Sci, 11(8), 342-8. doi:10.1016/j.tics.2007.06.009.

Numerous literature has examined has supported the notion that maintenance of physical activity levels can improve if not sustain cognition and brain function. Such studies were conducted under observational human studies, clinical trials and animal research to determine molecular and cellular mechanisms (Kramer & Erickson, 2012).

Observational Studies

Kramer, A. F., & Erickson, K. I. (2012). Capitalizing on cortical plasticity: influence of physical activity on cognition and brain function. Trends Cogn Sci, 11(8), 342-8. doi:10.1016/j.tics.2007.06.009.

Studies conducted concluded after a follow up after 6.2 years of 158/1740 individuals developed dementia. These individuals were 34% less likely to exercise three times per week. The relationship between fitness and cognitive ability was stronger in objective measures than subjective (Kramer & Erickson, 2012).

Randomized clinical trials

Kramer, A. F., & Erickson, K. I. (2012). Capitalizing on cortical plasticity: influence of physical activity on cognition and brain function. Trends Cogn Sci, 11(8), 342-8. doi:10.1016/j.tics.2007.06.009.

These trials were conducted using randomized aerobic exercise interventions. The results were mixed due to lack of operational definition of cardiorespiratory fitness (determined by VO2 max), length and intensity, cognitive processes examined and other confounding variables such as age, health and socioeconomic status. Regardless, there was a moderate effect size for treatment interventions on normal (including decline of executive cognitive processes) and pathological cognitive processes. There is still little significant evidence supporting cognitive change, because of the reductionist nature of the study. Furthermore, fitness effects are not discriminate of a specific brain function. What can be concluded using functional magnetic resonance imaging (hereinafter fMRI), showed that through a six month aerobic exercise intervention (walking, stretching) of one hour per day; increased gray matter volume in the frontal and temporal cortex and white matter in the anterior region of the brain. The underlying mechanism remains an anomaly. The changes in volume may be indicative of enhanced cognitive performance.

Animal Research

Kramer, A. F., & Erickson, K. I. (2012). Capitalizing on cortical plasticity: influence of physical activity on cognition and brain function. Trends Cogn Sci, 11(8), 342-8. doi:10.1016/j.tics.2007.06.009.

The use of animal research may serve as a great adjunct to human trials, such that it allows for better manipulation of otherwise uncontrollable variables such as: molecular and cellular mechanisms. Through this form of research it enhances our examination of factors that influence the brain and cognition. The study using lab mice is conducted over a 45 month period with access to voluntary aerobic exercise (wheel running). These mice had faster acquisition of mazes relative to their sedentary partners. In summary, exercise improved learning and retention of tasks related to the hippocampus. The molecular mechanisms that explain this phenomenon is that exercise increases the activation of mRNA and brain derived neurotropic factor (BDNF) in the hippocampus, cerebellum and frontal cortex. BDNF can improve dendritic outgrowth and synaptic plasticity improving neural networks. Amongst many other things BDNF acts as a neuroprotector, protecting these networks. This can explain the maintained cognitive function with exercise irrespective of age. Lastly, exercise increase Insulin Growth Factor 1 (IGF-1). It is alleged that increases in IGF-1 through exercise induces angiogenesis (production of new blood vessels) and neurogenesis (production of neurons). Both may influence cognition in the sense that, increases blood flow to the brain region could bring vital nutrients while the production of neurons can replaces the atrophying ones as a result of age.

Personal Wellbeing – Improving the Psychosocial aspects

Eime, R. M., Young, J., Harvey, J. T., Charity, M. J., & Payne, W. R. (2013). A systematic review of the psychological and social benefits of participation in sport for children and adolescents: informing development of a conceptual model of health through sport. Int J Behav Nutr Phys Act, 10,135. DOI: 10.1186/1479-5868-10-98.

In one published systematic review of literature it is alleged that through analyses of mainly quantitative studies, the most common health benefit was associated with improved well-being. This was followed by decrease stress response, reduced distress, improved function in a social setting and vitality.

Saxena, S., Ommeren, M. V., Tang, K. C., & Armstrong T. P. (2005). Mental health benefits with physical activity. J Ment Health, 14(5):, 45-451. DOI: 10.1080/09638230500270776.

What is more, studies published allege that participation in a socially engaging manner can contribute to mental health and overall life satisfaction. This is argued my stating, group activities enhance social connectedness, social support groups and peer bonding (Eime et al., 2013). In another study physical activity is shown to enhance social participation, social skills and access to social support systems (Saxena et al., 2005).

Penedo, F. J., & Dahn J. R. (2005). Exercise and well-being: a review of mental and physical health benefits associated with physical activity. Curr Opin Psychiatry, 18(2), 189-93. DOI:10.1097/00001504-200503000-00013.

Randomized clinical trials of cross sectional and longitudinal studies that last at least twelve months demonstrate that physical activity may improve mood and decrease symptoms associated with depression and anxiety. This is especially true with major depressive; according to DSM classifications, who showed significant improvements relative to psychoactive treatments. Exercise in the form of running is inexpensive and easily accessible can enhance an individuals experiential well-being in addition to physical function. Shifting over to resistance interventions that occur over a 24 week period showed significant improvements in mood scores based on measurements obtained Exercise Induced Feelings Inventory. Yoga and other related non-traditional forms of physical activity showed significant decreases in perceived stress and negative affect.

Psychological Stress and Well-being in adolescents (Farbod)

Norris, R. Carroll, D. & Cochrane, R. (1992). The effects of physical activity and exercise training on psychological stress and well-being in an adolescent population. J Psychosom Res, 36(1): 55-65. DOI: 10.1016/0022-3999(92)90114-H.

Within the last 25 years there has been extensive research that attests to the association between stressful life events and ill-health. A study conducted with 147 adolescent subjects examined the effects of exercise stress. The results concluded that people who self-reported higher levels of physical activity also reported less stress and lower levels of depression. (Norris et al., 1992) The study looked at both high and moderate levels of intensity within aerobic training, flexibility training or a control group. Individual in the high intensity group experienced the greatest reduction in stress than the other groups. However, this initial change declined towards the end of the intervention program. (Norris et al., 1992) The moderate intensity group saw positive stress reduction effects of exercise which increased throughout the study. It is noted that exercise can diminish psychological stress if it is of sufficient intensity. Furthermore aerobic activities may result in positive psychological effects through measurable improvements of aerobic or physical fitness. (Norris et al., 1992)

Absence of Disease

Kramer, A. F., & Erickson, K. I. (2012). Capitalizing on cortical plasticity: influence of physical activity on cognition and brain function. Trends Cogn Sci, 11(8), 342-8. doi:10.1016/j.tics.2007.06.009.

In addition to maintenance of cognition and brain function, exercise can act as an adjunct in reducing prevalence or delayed progression of neurological diseases. Much of the establish literature focus their studies around dementia disorders including Alzheimer’s disease and other trauma related injuries to the brain.

It is widely established that being sedentary leads to an impairment of physical health, social engagement and occupational performance. It is also to be noted that along with the physical benefits of exercise there are psychological benefits included. Some may argue that these physical and psychological benefits are correlated. The issue with current research is determining the optimal dose and the underlying mechanism. Based on observation and cross-sectional studies that utilized a self-report method, such studies support the claim that better mental health is correlated with increased engagement of physical activity. What is more, such a study showed that two to four hours a week had the largest difference. In addition, 65% of adults who exercised less than four hours had poorer mental health. In general it is said that poor mental health was associated with exercise that was less than two or greater than seven hours per week. This can be visually demonstrated by an inverted “U” relationship. Anywhere in between this duration of exercise was 1.39 times more likely to have better mental health irrespective of socioeconomic status.

Saxena, S., Ommeren, M. V., Tang, K. C., & Armstrong T. P. (2005). Mental health benefits with physical activity. J Ment Health, 14(5), 445-451. DOI: 10.1080/09638230500270776.

The World Health Organization claims that 60% of the global population fails to achieve thirty minutes of physical activity daily, two thirds of that do participate in physical activity but do so insufficiently to obtain the associated health benefits. Physical activity is substantially low in the older age cohorts (44+ years old). With regular participation individuals are less likely to have major depression or a range of anxiety disorders classified by the DSM. The literature published surrounding this topic have shown an effect size of 0.72 moderate but borderline large, for treating anxiety and depression. It is important to note that this is less powerful than medication and psychotherapy. What is more, non-clinical volunteers, short follow up interviews, experimenter blinding may have led to some over-estimating. Another study conducted with exercise control groups and exercise with Sertaline (anti-depression medication) following a16 week duration at 70-85% max heart rate parameter showed that individuals in the exercise-medication group showed greater relapse into depression symptoms than the respective control group. With respect to, exercise being a prescription adherence to physical activity programs was higher when prescription was paired with a referral to an exercise specialist (8 months) compared to just a prescription from a doctor (6 months). (Saxena et al., 2005)

Mental Health and Physical Activity (Daniel)

Hansen, C. J., Stevens, L. C., & Coast, J. R., (2001). Exercise duration and mood state: How much is enough to feel better?. Health Psychol, 20(4), 267-275. DOI: 10.1037//0278-6133.20.4.267

This study examines the positive and negative effects from exercise on mental health. It also puts into consideration the recommended duration of the exercise and weather negative or impacts effects on mental health are associated with prolonged exercise or not.

+++ Positive effects of physical activity on mental health (Daniel)

Studies reported that physical activity is able to increase an individual’s mental health by affecting certain aspects in their life such as self-esteem, general well-being and satisfaction with physical appearance. Evidence was also found that physical activity has a protective effect against the development of depression, or that physical inactivity might be a risk factor for depression. (Hansen et al., 2001) Although the effects of physical activity have mainly been studied through aerobic exercise, evidence indicated that anaerobic physical activity; such a flexibility training or bodybuilding can also reduce depressive symptoms. (Hansen et al., 2001) Aerobic activity has also been shown to show improvement of depressive and anxiety symptoms after a single exercise episode has been reported occur and is seen to last for a couple of hours or even up to one day.

Mechanism of improved mental health (Daniel)

There have been psychological hypotheses that have been proposed to explain the beneficial effects of physical activity on mental health. We will add on to these psychological and physiological mechanisms further down.

  1. Distraction: this hypothesis suggests that the diversion from unfavorable stimuli leads to an improved mood during and after the exercise.
  2. Self-efficacy: this hypothesis proposes that, since physical exercise can be viewed as a challenging activity, the ability and mindset needed and taken to get into it leads to improved mood and self-confidence.
  3. Social Interaction: this hypothesis states how social relationships commonly inherent in physical activity, and the interactions that occur while exercises play an important role in the effects of exercise on mental health.

In addition to the psychological hypotheses, there have been several physiological hypotheses made to explain the effects of physical activity on mental health. The two that are the most studied are:

  1. Monoamines: this hypothesis is supported by the fact that physical activity increase the synaptic transmission of monoamines, which functions the same way as antidepressant drugs. This is why this hypothesis seems to explain the improvement of mood associated with physical activity.
  2. Endorphins: this hypothesis is based on the observation that physical activity causes the release of endogenous opioids (endorphins). These endorphins affect the central nervous system and are responsible for the sensation of the calm and improved mood experienced after exercise. Another speculation is that there is a possible relation between the increase restlessness, nervousness, irritability and feelings of frustration when physically active individuals withdraw from exercise. This would be due to the absence of endorphins in the individual.

Negative effects of physical activity on mental health (Daniel)

  1. Excessive Exercise: Physical activity can actually have a negative effect when the person becomes obsessed, resulting in an exaggerated preoccupation with exercise and excessive training. This condition has often been characterized as anorexia nervosa or as an addiction. The investigation of the definition of this has been split between individuals excessively exercise and have an eating disorder and those who do not.
  1. Muscle Dsymorphia: This is a condition of alteration of the body image amongst weightlifters and body builders, that even though these individuals are larger and muscular, they believe that they are weak and skinny. There have been some denominations suggested for this such as “bigamerexia” and “reverse anorexia”.
  1. Use of anabolic-androgenic steroids: The need to see results faster, or make more significant gains causes some physically active people to use steroids. This can make them more irritable and aggressive, which might also provoke some users to commit criminal acts. The users also experience depressive like symptoms in the periods of absence.
  1. Overtraining syndrome: Most athletes actually experience mood deterioration without impairment in sport performance the longer and more intense they go within their workouts. This is because in order to reach there goal for improved performance they have to push themselves to his or her physical capacity. In the situations of excessive training, the athlete does not get sufficient rest, and starts to experience problems such as sleep disturbance, loss of weight and appetitive, reduced libido, irritability, heavy and painful musculature, emotional liability, and even depression.

Alzheimer’s Disease (Daniel)

World Health Organization. (2009). The Role of Physical Activity in the Prevention and Management of Alzheimer’s Disease - Implications for Ontario. DOI: 10.2236/bmj.b158.

Alzheimer’s disease is classified a progressive neurodegenerative condition distinguished by changes to brain structure and function. Changes in structure and function may give rise to emotional, neurocognitive and physically complications results in a reduction in the quality of life, decrease functional mobility and increase reliance on others. Depression like symptoms are up to ten times more likely to happen to an individual with AD then one of the general population. Approximately 15% of the 747000 seniors in Canada are living with some form of dementia or cognitive impairment. Alzheimer’s can be defined by three progressive and overlapping phases of impairment:

  1. Preclinical Alzheimer’s disease
  2. Mild Cognitive Impairment due to AD
  3. Dementia due to AD

In the early stages of this sickness, it can often be misdiagnosed and attributed behaviour changes, attention deficit, and forgetfulness. Since at the early stages this disease is often misdiagnosed, the most effective way of diagnosis is through a detailed examination of brain tissue via biopsy. Other non-evasive approach include: a detailed medical history and physical examination in order to identify family history of dementia, changes in behavior, mood, and motor performance or brain imaging.

Risk Factors (Daniel)

Herrmann, N., Tam, D. Y., & Balshaw, R. (2010). The relation between disease severity and cost of caring for patients with Alzheimer disease in Canada. Canadian Journal of Psychiatry, 55(12), 768-75.

There is to some degree about non-modifiable risk factors such as age decline. However, there is also compelling research that exercise increase the production of Brain derived neurotropic factor that may improve cortical plasticity and enhance, maintain or prolong age related cognitive decline (Herrmann et al., 2010) (Kramer & Erickson, 2012). Conversely other factors include family history, mild cognitive impairment, head trauma, traumatic brain injury and the presence of a certain genetic variant recognized as apolipoprotein (Herrmann et al., 2010). There are also some chronic disease risk factors such as physical inactivity, diabetes, smoking, abdominal obesity, and high cholesterol (Herrmann et al., 2010). Note that a majority of these diseases can be avoided by maintaining physical activity levels. Management of AD is still difficult, because it is limited to three main drugs. Other approaches however include a therapeutic approach such as group-based activities such as art and music, cognitive approaches, and emotion oriented therapy (Herrmann et al., 2010). Perhaps the biggest opportunity still seems to be physical activity earlier and later on in individual’s lives to prolong age-related cognitive disease.

Physical Activity and Alzheimer’s disease (Daniel)

De la Torre, J. C. (2009). Cardiovascular risk factor and therapeutic target in neuropathology, including Alzheimer’s disease: a systematic review of the literature. Cardiovasc Psychiatry Neurol, 23(1), 1-10. DOI: 10.1155/2012/367516.

Although the research is not definitive from human and animal research there is claim that regular physical activity can be beneficial for the prevention and management of Alzheimer’s disease. Moderate to high level of aerobic exercises can actually improve the quality of life; maintain functional performance and positively impact mood and depressive symptoms of Alzheimer patients (De la Torre, 2009). Some research published suggests that physical activity promotes the maintenance of grey matter brain volume, and slow the rate of cognitive decline which is an asset for people with AD (De la Torre, 2009) (Kramer & Erickson, 2012). Physical activity has also been associated with increased resistance to oxidative stress, and to produce more efficient metabolism. Cardiovascular health and fitness has been related to better cognitive outcomes, lower age related brain atrophy, plasticity, and improved cerebral blood flows (De la Torre, 2009) (Kramer & Erickson, 2012). All aforementioned earlier in the age related decline. Albeit the research is new, it provides compelling evidence of the benefits of physical activity on cognitive disorders. The higher the physical activity the person with AD partakes in the higher is chances are to have prolonger survival with AD, and to lower the risk of dementia related deaths.

Physical Activity as a treatment for Alzheimer’s Disease (Daniel)

Maci, T., Pira, F. L., Quattrocchi, G., Nuovo, S. D., Perciavalle, V., & Zappia, M. (2012). Physical and Cognitive Stimulation in Alzheimer Disease. The GAIA Project: A Pilot Study. Am J Alzheimers Dis Other Demen, 27(2), 107-113 DOI: 10.1177/1533317512440493.

This study explored the effect of physical activity for patients with Alzheimer’s disease in order to try finding a way or solution to trying to cope with symptoms associated with Alzheimer’s such as depression for instance.

The first result was PA as treatment for depression in AD patients:
This study first started by pooling together five different studies that measured depression with the Alzheimer patients before and after the intervention of physical activity. The analysis made showed an overall Standardized Means of Difference (SMD) of 0.84 which shows significant reduction of depression through PA in AD patients27 (Maci et al., 2012).

The second result was the PA Improves Activities of Daily Living (ADL) scores in AD patients:
The activities of daily living vary from personal care and function activities require for people to be living independently daily. Such as bathing, dressing, meal preparation, house care). The study shows that the intervention of physical activity improved the activities of daily living score for the Alzheimer patients. This is shown by an SMD of -0.65, which shows the significance of the intervention of PA in daily activities (Maci et al., 2012).

Third, it shows the PA improves the Quality of Life in AD Patients:
Studies have showed the SMD for physical activity intervention in relation to the QOL of the Alzheimer patients to be -0.82. However should be weary of this result because in an another study the result was negative showing the PA intervention this not make a positive impact.

Exercise

Operational Definition of Exercise or Physical Activity

Carek, P. J., Laibstain, S. E., & Carek, S. M. (2011). Exercise for the treatment of depression and anxiety. Int J Psychiatry Med, 41(1),15-28. DOI: 10.2190/PM.41.1.c.

Physical activity simply defined by some independent studies refers to it as “a form of bodily movement produced by skeletal muscles that results in energy expenditure beyond resting level” (Carek et al., 2011). They go further to draw a distinction between the latter and exercise it must be: planned, structured, repetitive and purposeful subset of physical activity (Carek et al., 2011).
The World Health Organization provides us with a good backdrop into some of the concepts used in physical activity.
Physical Activity has different modalities, researchers try to explore these different modes of exercise to establish a dose-response that is critical to developing an exercise prescription for individuals.

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You may hear these terms used a lot and this will provide us a foundation with respect to defining Exercise:

  • Type of physical activity - can take many forms: aerobics, strength, flexibility and balance are commonly used (WHO, 2010).
  • Duration - length of time that an activity has been performed for (WHO, 2010).
  • Frequency - The number of times an activity is performed, commonly expressed in bouts per week or sessions (WHO, 2010).
  • Intensity Level - Usually indicates the level of effort exerted in an activity performed there are three types; two that comprises our main focus:
    • Moderate - WHO classifies moderate-intensity PA as 3-6 times the intensity of rest, and usually is rated 5 or 6 on a 0-10 scale based on personal capacity (WHO, 2010).
    • High Intensity - WHO classifies this as 6+ times the intensity at rest, and usually equates to a 7-8 on a scale of 10 based on personal capacity (WHO, 2010).
  • Volume - Volume specifically speaks to strength or aerobics, it is hard to conceptualize as it incorporates the three concepts above (WHO, 2010).

Canada Recommended Physical Activity Guidelines

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More information on this from the Canadian Society for Exercise Physiology Physical Activity Guidelines Glossary (CSEP, 2011).

How much and what kind of exercise should I be getting?

The Canadian Society for Exercise Physiology have gone through great lengths to improving the recommended guidelines for Physical activity.
This information can be found on very simple information posters on their website (CSEP, 2012).

Dose-response relationship between physical activity and mental health (Farbod)

Hamer, M., Stamatakis, E., & Steptoe, A. (2009). Dose-response relationship between physical activity and mental health: The Scottish health survey. Br J Sports Med, 43(14), 1111-1114. DOI: 10.1136/bjsm.2008.046243.

There is an agreement with published literature that physical activity has positive effects on mental health. However there is a lack of consensus on how much and what type of activity and the optimal amount to achieve these benefits. A study looking at the Scottish Health Survey looked at the association between mental health and physical activity behaviours in a representative sample of 19 842 men and woman in order to obtain information on mental health. The study found that any form of daily physical activity was associated with a decreased risk of psychological distress. Using statistical procedures to fix cofounding variables such as: age, gender and social economic group the study determined that a moderate dose-response existed with small changes in psychological distress were observed. The different type of activities included domestic house work, walking and sports each independently associated with decreased odds of psychological distress. The greatest effect was seen from sports. Previous studies have determined the positive result of physical activity on mental health but have not yet been able to clearly outline the amount and type of physical activity to engage in. This study shows that individuals who participate in at least 20 min of physical activity of any sort per week will reap the benefits of lower levels of psychological distress. A dose-response pattern was demonstrated with great risk reduction for activity at a higher volume and/or intensity. Meaning that the longer or more intense the activity session the greater the reduction of psychological distress and greater improvements in mental health.(Hamer et al., 2009)

What are the many ways to get Physical Active?

Effects of acute exercise on mood and well-being (Daniel)

Peluso, M. A., & Guerra de Andrade, L. H. (2005). Physical activity and mental health: the association between exercise and mood. Clinics (Sao Paulo), 60(1), 61-70. Retrieved from: http://www.scielo.br/scielo.php?pid=S1807-59322005000100012&script=sciarttext

This experiment was set up to determine if acute exercise (=30 min of walking @ 60-70% of max. heart rate) will have an effect on patients with major depressive disorders. The study consisted of 40 participants 15 male and 25 females with a mean age of 38.1 years. The demographics of this study was as follows 68% were white, 17% were Latino, 11% were African American, and the final 4% designated themselves as other. People excluded from the study were ones who were reported to be regularly exercising 1 month before the screening, people intolerant or resistant to exercise, and participants with a principal psychiatric diagnosis other than major depressive disorder or who have a comorbid disorder and participants taking antidepressant medication. The participants were then split up into two groups one that is to be involved in an aerobic exercise and one a quiet rest control.
They assessed their state 5 min before exercise or control, 5, 30, and 60 minutes after. Both the Profile of Mood States (POMS) and the Subjective Exercise Experiences Scale (SEES) were given to ask the participants how they feel ‘right now at this moment’. Participants assigned to aerobic exercise were required to walk on the treadmill at a pace equivalent to 60-70% of their maximum heart rate and participants assigned to the quiet rest control were instructed to sit on a non-reclining chair for thirty minutes, they were not allowed to sleep or fall asleep.
Mood and well-being are primary dependent variables so no attempt was made to use clinical measures to assess the degree of their ongoing depression. The participants instead completed the subject exercise experiences scales (SEES) and the short form, 30-item profile of mood states (POMS).
The SEES showed satisfactory results with Cronbach alphas ranging from 0.77 to 0.84 in the experiments. The POMS demonstrated a Cronbach alpha correlation ranging from 0.93 to 0.95. The results for the experiment were that both groups showed a similar reduction in their measure of psychological distress, depression, confusion, fatigue, tension, and anger. However, on the exercise group reported a significant increase in their vigor and positive well-being scores.

Exercise Duration (Daniel)

Bartholomew, J. B., Morrison, D., & Ciccolo, J. T. (2005). Effects Of Acute Exercise On Mood And Well-Being In Patients With Major Depressive Disorder. Med Sci Sports Exerc, 37(12), 2032-2037. DOI: 10.1249/01.mss.0000178101.78322.dd.

This study was made in order to try and determine what length of time in one session of physical activity would be sufficient to show a positive mood improvement in a person. The Centers for Disease Control and Prevention and the American College of Sports Medicine shifted away their recommendation and emphasis of high levels of aerobic exercise and instead now recommend that 30 minutes or more of moderate intensity physical activity performed daily would be most beneficial for the health and fitness of adults. This accumulation may also be accomplished in short bouts throughout the day. Moderate intensity exercise has been identified to be performed at 60-75% of your maximum heartbeat.
This study only examined female participants in order to be thorough with results. They hypothesized that in all exercise trials; the participants would show a significant decrease in negative mood states in compared with participants in the resting control trails. They also hypothesized that as the length of exercise increases, the degree of the participant’s mood improvement will increase. This study involved 21 college students ages 20-26 years of age. Each participant that completed the study was given $10 gift certificate, as well as a course credit in there undergraduate course.
They used the Physical Activity Readiness Questionnaire (PAR-Q) in order to screen participants of any history of physical problems that would be an issue to the aerobic exercise. Mood state was measured using pre and post self- report POMS test.
The participants then exercised either alone or isolated in separate parts of the exercise facility were they couldn’t interact with another person. They were all tested at the same time each day for 4 consecutive weeks. Test 1 was sitting quietly for 30 min facing a third floor window. Test 2 was a warm-up on the bicycle in order to bring HR to 60% of maximum for ten minutes. Test 3 is a warm up to bring HR to 60% of estimated maximum and maintain that level while pedaling on the bicycle for 20 min. Test 4 the final test was a warm up to bring HR to 60% of estimated max while marinating it for 30 min.
The results of the study showed that improved levels of vigor with reduced levels of confusion, total negative mood and fatigue. Planned analyses showed that the improvements in fatigue, vigor, and total mood that occurred after 10 minutes of exercise. These improvements were seen for over 20 minutes after the exercise session.These results satisfied the current recommendation which suggest that in order to experience positive fitness and health benefits, healthy adults need to participate in a total of 30 minutes or more of moderate physical exercise daily, or accumulated in short bouts throughout the day.

Aerobic Exercise (Farbod)

Ferdowsi, M. H., Marashian, F., & Marashian, H. (2010). The effects of 12-week aerobic exercises on rate of mental health in male students of ahvaz payam noor university. Human Movement, 11(2), 167-171. DOI: 10.2478/v10038-010-0021-3.

Aerobic exercise is associated with long term activities that require oxygen uptake for performance. In this form of physical activity the muscles are supplied with oxygen by means of blood circulation. This form of aerobic metabolism can be established through low intensity training lasting for long durations of time. An investigation studying the effects of a 12-week aerobic exercise program found improvements in mental health and self-esteem. The treatment group showed improvements in depression, physical stress and social desirability. Physical benefits are closely related to mental health, enhancing the self-reported self-efficiency and self-control where these feeling will lead to an increase in self-confidence and self-esteem. The authors of the study believe that the main reasons for the effect of physical activity on mental health is through the influence of attitudes and positions of people created by the positive mood that exercise induces via endorphin release, social achievements and reduction in tension and depression.

Yoga and Mental Health (Farbod)

Sistig, B., Lambrecht, I., & Friedman, S. H. (2014). Journey back into body and soul - an exploration of mindful yoga with psychosis. Psychosis, doi: 10.1080/17522439.2014.885556.

Yoga has become an increasingly popular form of physical activity in the west, with emerging evidence on its benefits for both the body and the mind. A study done in New Zealand explored the effectiveness of a yoga intervention program in a mental health rehabilitation center. The study ran for 7 weeks with two 30 minute sessions each week and found four interesting themes:

  • Relaxation. From week one participant’s reported an increased sense of relaxation and rejuvenation and improved fitness towards the end of the program.
  • Calmness / reduced stress. The participants described feeling more calm, serene and peaceful indicating greater self-acceptance and coping strategies.
  • Energy and focus. There was an increase in perceived vitality and focus particularly for individuals who experienced sleepiness and dizziness.
  • Motivation to engage with life. Participants described themselves as having more motivation and a more positive outlook on the day. A correlation between decreased anxiety and increased motivation to engage in daily activities was suggested.

This study demonstrates that yoga is potentially a viable adjunct for treating people with psychosis, suggesting that yoga does indeed have a positive effect on mental health. Another significant result of the study is the self-reported temporary absence of auditory hallucinations. Being able to maintain a mental state of peacefulness is subsequently promising.

Gender differences (Farbod)

Asztalos, M., De Bourdeaudhuij, I., & Cardon, G. (2010). The relationship between physical activity and mental health varies across activity intensity levels and dimensions of mental health among women and men. Public Health Nutr, 13(8), 1207-1214. DOI: 10.1017/S1368980009992825.

In a study to explore the gender-specific variations related to the intensity of physical activity. A relationship with mental health has demonstrated difference between the mental health of men and woman in relation to intensity levels of different activities. In men there appears to be an inverse relationship between the high-intensity physical activity and feelings of depression and symptoms of somatisation. In addition, men there seems to be no significant difference in emotional well-being with respect to the intensity of physical activity but there are differences in psychological complaints showing a significant relationship with high-intensity activity. In women there were positive associations between walking and emotional well-being and an inverse relationship between moderate-intensity physical activity and symptoms of somatisation. There was a positive relationship between well-being and walking and differences in psychological complaints were significant for moderate levels of physical activity. This study suggests that in the general population, the physical activity and mental health relationship is always positive regardless of the intensity level of the activity. In men, it addresses symptoms and palpable discomfort and the optimal level of physical activity is high (vigorous). In women, it addresses complaints but also distresses including lower mood, disturbing anxiety and altered well-being with mild-intensity of physical activity.

A number of studies have shown an inverse relationship between physical activity and depression and anxiety. The mechanisms underlying these relationships are not well understood. A study of 2055 adolescents suggests that participation in physical activity is indirectly associated will lower levels of psychological distress through a positive evaluation of one’s appearance. This self-perception was dependent on gender, female adolescents showed a greater indirect effect than males (Haugen et al., 2014). This may indicate that the mechanism lies within a moderator. Participation in physical activity during adolescent years suggests an improved ability for young people to maintain a satisfying level of appearance evaluation, allowing them to better prepare themselves to cope with psychological distressing disorders (Haugen et al., 2014). Having a better understanding of these mechanisms is important for the development of optimal intervention programs.

Effects of Exercise Hypotheses

Crocker, P. R. E. (2013). Exercise and Mental Health. Leith, L. M., Kerr, G. A., & Faulkner, G. E. (Eds.), Sport and Exercise Psychology Custom Edition (pp. 3-26). Boston, Massachusetts.

Physical activity has many benefits as we have explored, with compelling evidence supporting psychological benefits from running interventions. We will attempt to explore some exercise-psychological benefits hypothesis.

  • Expectancy Hypothesis - individuals expect to feel better so they report (self-report studies) feeling better.
  • Sense of Mastery (self-efficacy) - Humans are motivated by a sense of accomplishment. Exercise allows us to gain this, which makes us feel better.
  • Thermogenic Hypothesis - Increases in body core temperature is related to reductions in muscle tension, as a result we feel relaxed, enhanced mood and reduced anxiety.
  • Endorphin Hypothesis - The release of endorphins (ex. endogenous opiates like dopamine) during exercise may result in positive mood effects. However, research from human trials are inconclusive.
  • Serotonin Hypothesis - Neurotransmitters modulates mood, emotion and sleep. These neurotransmitters are increased during exercise and could be responsible for self-reported scores. It is important to note SSRI's (selective serotonin re-uptake inhibitor) prevent the re-uptake of these neurotransmitters, prescribed anti-depressants utilize this way to treat or alleviate depressive symptoms.

Farbod

Salmon, P. (2001). Effects of physical exercise on anxiety, depression, and sensitivity to stress: A unifying theory. Clinical Psychology Review, 21(1), 33-61. DOI: 10.1016/S0272-7358(99)00032-X.

There is an extensive amount of research done on the effects of exercise and its effects on the mind and body. A unifying theory based on the effects of exercise must incorporate key features of evidence which include:
(1) Exercise is aversive, but it also has positive hedonic properties, most effectively after physical activity
(2) Physical activity has anti-depressive and anxiolytic effects
(3) Physical activity reduces sensitivity to stress

Suggestion for future Research

A challenge of the unconscious and conscious mind (Farbod)

Despite the well documented effects/benefits of physical activity only a small portion of the population, about one fifth, are regularly engaged in such activities. So why do so many people fail? The root of this problem is psychological and related to the processes of the unconscious and conscious mind. It is thought that unconsciously operating motives are capable of inhibiting the initiation of exercise interventions and adherence to such programs. If the behaviour is repeated over long periods of time situational cues can prompt certain activities as it is the case for those people who regularly participate in physical activity. There is some evidence suggesting that the unconscious mind actually works against exercising by acknowledging cues and excuses for not being active. A related problem for both the conscious and unconscious mind is the threat to an individual sense of freedom and choice that it poses, exercise can become a true choice or it can hinder other activities that one might choose to do. While most people know the multiple benefits of exercising they pursue it as a means towards an end, such as to lose weight. In doing so, individuals struggle cognitively for their need with self-governance while balancing their personal and leisure activities depleting them of the finite self-control they possess making them more vulnerable to temptations. In conclusion, both the conscious and unconscious mind fail to turn most people into rational thinkers who would do what is best for their health.

Theories and models leading to motivation or behavioural changes

Crocker, P. R. E. (2013). Motivation and Behavioural Change. Mack, D. E., Sabiston, C. M., McDonough, M. H., Wilson, P. M., & Paskevich, D. M. (Eds.), Sport and Exercise Psychology Custom Edition (pp. 111-116, 119-123). Boston, Massachusetts.

With this section we will attempt to explain how individuals initiate and adopt physical acitivity

Transtheoretical model

This model proposes individuals move through non-linear temporal stages, each stage is approximately 6 months and relapse is possible in all stages.

  1. Pre-contemplation - individuals do not consider behaviour change in the next six months
  2. Contemplation - individuals are taking into serious consideration behaviour change in the next six months
  3. Preparation - individuals have taken small changes towards action
  4. Action - individuals have been engaging in behaviour changes for the past six months
  5. Maintenance - individuals have been engaged for more than six months

Applications for Physical activity Interventions

  1. Pre-Contemplation - provide information about physical activity to bring about awareness
  2. Contemplation - challenge individuals to see the benefits of physical activity in order to really push them into preparation
  3. Preparation - help organize a plan, this assistance is to prevent relapse which is greatest in preparation phase
  4. Action - Provide tips on how to overcome barriers
  5. Maintenance - assist with coping, alternatives and avoiding relapses

Theory of Planned Behaviour

TPB.jpg

Personal and social factors influences our intentions which in turn have an effect on our behaviours. This theory stipulates that the most important determinant is our own intentions. It is important to note that there are temporal fluctuations, that is the longer between intention and behaviour will result in no adherence to an intervention program.
Main points of Theory of Planned Behaviour:

  • Attitudes - evaluations of engaging in a behaviour (either negative or positive)
  • Subjective norms - individuals percieved social pressures to perform a behaviour. This can come from personal factors (family, physicians) or the environment.
  • Percieved Behavioural Control - reflects that behaviour should be voluntary and can be thought indirectly and directly affect behaviour.

Each of the three factors above contain underlying beliefs that are reflective of intention,

  • Behavioural beliefs are beliefs that changes in behaviour will result in a certain outcome (ex. exercise has many positive health benefits).
  • Normative beliefs reflect an individual’s perceptions of a significant other and the values they have invested in the chosen behaviour (ex. social pressures of family and friends).
  • Control beliefs are an individuals perceived barriers (lack of time) or facilitators (opportunities) to engaging behaviour.

Self-determination theory

The main focus of this theoretical framework is to the extent that behaviours such as sport and exercise should be solely voluntary, as opposed to being controlled by an external agent. Furthermore, this model has two main concepts which will be explored into in detail:

Organismic Integration theory

Organismic Integration theory is one framework that claims motivation is a multidimensional construct, where motives range from autonomous (self-determined) to controlling (least self-determined)

SDT.png
  • Amotivation is the absences of motivation, where an individual perceives no connection between actions and outcomes.
  • Extrinsic Motivation
    • External regulation: Actions performed to achieve an external demand, reward or to avoid punishment.
    • Introjected Regulations: Actions are to avoid negative emotions or maintain a fragile sense of self-worth.
    • Identified Regulation: Actions are driven by personal importance or values.
    • Integrated Reguation: Actions are driven by beliefs about oneself or identity.
  • Intrinsic Motivation: Actions are performed for inherent interest, satisfaction and enjoyment

Basic needs theory

This framework believes that all humans have three basic psychological needs, that when fulfilled facilitate the internalization of motivation.

  • Competence is concerned with feelings of being capable of undertaking challenging tasks
  • Autonomy is the feeling of one having ownership over their behaviours.
  • Relatedness is concerned with feeling meaningfull connections between behaviours and the environment

Eastern medicine (shanice)

Chan, Cecilia; Ho, Petula Sik Ying; Chow, Esther.Social Work in Health Care34.3-4 (2001): 261-282.

Under the division of labor of Western medicine, the medical physician treats the body of patients, the social worker attends to their emotions and social relations, while the pastoral counselor provides spiritual guidance. Body, mind, cognition, emotion and spirituality are seen as discrete entities. In striking contrast, Eastern philosophies of Buddhism, Taoism and traditional Chinese medicine adopt a holistic conceptualization of an individual and their environment. In this view, health is perceived as a harmonious equilibrium that exists between the interplay of 'yin' and 'yang': the 5 internal elements (metal, wood, water, fire and earth), the 6 environmental conditions (dry, wet, hot, cold, wind and flame), other external sources of hann (physical injury, insect bites, poison, overeat and overwork), and the 7 emotions (joy, sorrow, anger, worry, panic, anxiety and fear). The authors have adopted a body-mind-spirit integrated model of intervention to promote the health of their Chinese clients. Research results on these body-mind-spirit groups for cancer patients, bereaved wives and divorced women have shown very positive intervention outcomes. There are significant improvements in their physical health, mental health, sense of control and social support. [4]

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