The benefits of exercise and movement on wellbeing and mental health

“If scientists developed a pill that reproduced all the benefits from exercise, we could treat many diseases.”

Author; Irene Molina-Gonzalez

In human history, natural selection was defined as the survival of the fittest. Physical activity was essential to hunt for food and escape from predators (1). Our metabolism developed to store energy and have a superior endurance capacity to chase food (1); therefore, our normal biological condition is an exercise-trained state. Physical exercise is not something we only need to do because of our nature but also because of its many health benefits.

Physical inactivity is considered one of the most significant public health problems in the 21st century (2). Our genetic adaptations to physical activity mean that a lack of exercise can lead to negative body changes, increasing the risk of obesity, diabetes, and cardiovascular and cardiorespiratory diseases. Additionally, this sedentary lifestyle can negatively impact mental health and increase the risk of cancer and cancer-related deaths, ultimately affecting overall quality of life.

Benefits of exercise in physical health

Exercise can help control many chronic and inflammatory diseases, improving health and increasing longevity. It’s been suggested that exercise can partially reverse the effects of aging (3). One such example is by protecting telomeres from degradation. Telomeres function as caps at the terminal portion of chromosomes to protect our DNA (which contains the information of all our body) from damage and degradation. With age, telomere length decreases and can be accelerated by a poor lifestyle and disease. For many years, research has studied how to preserve telomeres to improve health and longevity. Studies observed that exercise may positively affect preserving telomere length (4-7), where the telomere length of physically active people is comparable to 10-year-old younger sedentary individuals (7).

Age-related muscle loss, known as sarcopenia, occurs during aging and leads to decreased muscle strength, mobility, and independence. Moreover, reduced strength, measured by grip strength, is associated with a higher incidence and mortality of dementia (8) and increased depression and anxiety (9). Regular exercise can prevent or slow down sarcopenia, especially resistance training. Mixing other activities like aerobic exercise, balance or endurance alongside resistance training has also been shown to help build and maintain muscle mass (10,11).

Physical exercise can improve bone health and reduce the apparition of some bone conditions like osteoporosis. Osteoporosis is a disease of the bones in which they weaken, become more fragile, and break more easily. Osteoporosis is highly prevalent among postmenopausal women. Exercise interventions improve bone density in postmenopausal women, decreasing fracture risk (12). A proposed mechanism by which exercise increases bone health is by increasing bone mineral content and density (13). Moreover, exercise can also improve bone health during development. The high impact and mechanical force generated from physical activities like running and jumping during growing periods improves bone quality and strength (14,15).

Exercise reduces cardiovascular disease and related mortality. For instance, populations who lead an active lifestyle, such as horticulturalists, pastoralists, or farmers, have a lower incidence of developing conditions like stroke, coronary atherosclerosis, metabolic syndrome, or ischaemic heart disease. Physical exercise strengthens the myocardium (cardiac muscle), reverses myocardial stiffness by increasing collagen and elastin content, and prevents heart failure (16). Exercise improves endothelial, the cells lining the blood vessels, function and structural vascular adaptation, improving blood vessel functions (16). These adaptations improve blood flow and protect against arrhythmias. Exercise induces the myocardium to release anti-inflammatory and protective molecules (16). The benefits of aerobic exercise on cardiovascular health have been well-documented (17). However, ongoing clinical trials are exploring the impact of combining various training modalities to develop better strategies for safeguarding public health against cardiovascular disease (18).

Moderate exercise may decrease the risk of developing some types of cancers (3), such as lung (19), colon (20), breast (21), ovarian (22,23) and pancreatic cancer )24). Studies on breast cancer survivors have observed that a minimum exercise routine is sufficient to lower recurrence and mortality (25). These beneficial effects are produced by regulating immune cells’ functions, reducing malignant tumour progression (26,27). Moreover, it can be applied to reduce fatigue due to cancer treatments (28,29). Fatigue can relate to low levels of dopamine (30,31), a neurotransmitter (a molecule transferred between the nerves in our body necessary for nerve function) that regulates motivation and mood. Physical activity promotes the release of dopamine. During a moderate exercise routine like swimming, dopamine has been shown to exhibit antitumor functions by reducing tumour growth and lung metastasis (32).

Exercise and brain health

Engaging in physical has numerous benefits for the body and brain health. It can decrease the likelihood of developing neurodegenerative diseases such as certain types of dementia, balance neurotransmitters, and enhance mood while reducing symptoms of depression.

During aging, there is a loss of cognitive functions. This is associated with a decreased brain volume, reduced blood flow and molecular changes, which cause impaired neuronal survival and synaptic (the connection between neurons) loss. These changes, alongside increased inflammation and abnormal protein aggregations, are more pronounced in Alzheimer's disease (AD) and other types of dementia (33). Physical exercise can attenuate or reverse these changes. Physical activity increases neurogenesis (the birth and formation of new neurons) in the hippocampus, an important brain area for learning and memory (34). Large human studies comparing long-distance cross-country skiers with the general population observed that skiers presented a lower risk of developing vascular dementia (35). Clinical trials on patients with mild-to-moderate Alzheimer's disease have shown that engaging in aerobic exercise can improve memory, reduce hippocampal atrophy, and increase cardiorespiratory fitness. This suggests that aerobic exercise may be beneficial in reducing cognitive decline in these patients (36,37). Research conducted on rodents has shown that mice who engage in voluntary wheel running, also known as marathoner mice, have higher levels of anti-inflammatory molecules in their plasma than sedentary mice. When the plasma from these marathoner mice was transferred to a mouse model of AD, it decreased inflammatory gene expression. Additionally, humans with cognitive impairment who participated in a structured exercise routine had the same anti-inflammatory mediators in their plasma as the marathoner mice (38).

Physical exercise can help with mental health and well-being in the general population. Studies done on pupils have seen that exercise improves motivation and general well-being regardless of intensity (39,40). These benefits may be associated with brain structural changes. Brain imaging studies on young adolescents have shown that regular moderate or vigorous physical activity significantly impacts brain structure, microstructure, and function. This includes increased grey matter volume and cortical area and improved blood flow. This study also found changes in white matter patterns associated with increased macroglia cells like astrocytes and oligodendrocytes, cells vital for brain physiology and myelin plasticity being processes required for learning (41). Physical activity is a potent tool to elevate mood, reduce stress, improve sleep, and increase self-esteem. Current clinical trials are testing protocols to incorporate exercise routines as a treatment for depression. Physical exercise has been proposed to have the same or improved effects on depressed patients as antidepressant treatments (42).

Image of an oligodendrocyte (a brain cell) in laboratory conditions

Incorporating exercise into your daily routine

It's been established that exercise is crucial for overall health and wellness. The World Health Organization (WHO) has laid out guidelines for minimum physical activity levels, which vary by age group. Children and young people between the ages of 5 and 17 should engage in at least 60 minutes of moderate to vigorous exercise daily, while adults over 18 should aim for at least 150 minutes of moderate to vigorous exercise or 75 minutes of intense physical activity per week. Exceeding these amounts can provide even more health benefits. Individuals unable to meet these recommendations due to health issues should strive to remain as active as possible (43).

There are numerous ways to include physical activity in your daily routine, such as taking a brisk walk, hiking with friends, joining a running club, dancing, swimming, or attempting aqua aerobics for low-impact exercise. Begin with achievable goals that match your present fitness level and schedule. Set small deadlines and take pride in yourself every time you complete your activity to stay motivated and share your progress with others. However, always remember to do it for yourself and for the numerous benefits it brings.

References

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