[Lauren Cowley is currently a senior at the University of Mount Olive and will graduate in May 2017. She is an Exercise Science Major, and a former NCAA DII Soccer Player. She is currently an Athletic Development Intern at Athletic Lab.]

We’ve all seen how it happens, January comes around and suddenly the gym is full of people, the streets and parks are filled with runners and walkers, all attempting to fulfill their new year’s resolution of losing weight or achieving the ‘new year, new me’ status. Then suddenly summer creeps around, and this all happens again with people attempting to lose weight with the aim to fit into that one dress, to look better on the beach on vacation, or even wanting to avoid the embarrassment of not feeling comfortable in summer clothes. First of all, I applaud each and every person who engages in exercise, for taking that step and going to the gym, or for a run, or even just a walk. For some, that’s the hardest step of all.

Exercise has a multitude of established benefits with minimal negative side effects. These benefits include: weight control, improved body composition, decreased risk of obesity and diabetes mellitus, improved coronary benefits, lower blood pressure, decreased risk of osteoporosis and cancer, improved psychological wellbeing, improved overall quality of sleep and improved cognitive function. Exercise is extremely cost-efficient and is widely accessible at a societal level. Regardless of age, gender or physical ability, everyone and anyone can benefit from exercise. Which is why exercise is commonly regarded as medicine and regularly prescribed by medical practitioners.

Through these extensive benefits, an improvement in overall health status and thus, a reduction in risk of chronic diseases and disability can be seen. Regular physical activity has proven to be effective in the primary, and secondary, prevention of multiple chronic disease and chronic death. Simply by increasing one’s energy expenditure from physical activity by 1000kcal per week, or increasing physical fitness by one MET, a mortality benefit of 20% can be obtained (Hu et al., 2004). Whilst, by as little as just walking at least 2hrs per week is associated with a reduction in the incidence of premature death of 39-54% from any cause (Gregg et al., 2003).

One benefit, a benefit of which the majority of people who do engage in exercise do it for, is that exercise is extremely beneficial for weight control. Through burning calories whilst participating in physical activity, a potential calorie deficit may be achieved, resulting in the loss of weight. This enhanced weight control can potentially lead to improved body composition. Body composition is improved through reducing fat mass, particularly abdominal adiposity, typically achieve through improved weight control. O’Leary et al (2006) discovered an exercise training-induced reduction in visceral fat, abdominal subcutaneous fat, and total abdominal fat (O’Leary et al., 2006).

Through this enhanced weight control and body composition improvements, effective prevention of obesity can be experienced. Through the prevention of obesity and routine physical activity, the risk of developing type 2 diabetes mellitus can also be decreased.  With each increase of 500kcal in energy expenditure per week, being associated with a decreased incidence of Type 2 Diabetes by 6% (Helmrich et al., 1991). The relationship between physical activity and the risk of type 2 diabetes has been frequently correlated, with Sigal et al. (2006) discovering that a minimum of 150 minutes of physical activity per week reduces high risk population’s likelihood of developing type 2 diabetes by 58% (Sigal et al., 2006).

In terms of coronary health benefits, being fit and active alone is associated with a greater than 50% reduction in the risk of cardiovascular disease (Myers et al., 2004). Whilst, routine physical activity can also result in improved lipid lipoprotein profiles. This can be achieved through decreasing triglycerides levels, increasing HDL (high density lipoprotein) concentrations and decreasing LDL (low density lipoprotein) concentrations. Spate-Douglas and Keyser (1999) found that moderate intensity exercise, exercise done at 40-60% V02R, was sufficient to improve one’s HDL profile (“Exercise Intensity: Its Effect on High-Density Lipoprotein Profiles,” n.d.).  Similarly, Adamopoulos (2001) also found that physical training benefits peripheral inflammatory markers reflecting monocyte/macrophage-endothelial cell interaction. So basically, that systemic inflammation was reduced through exercise (Adamopoulos, 2001).

Coronary blood flow can also be improved through exercise, as Hambrecht et al. (2000) discovered. Exercise improves endothelium-dependent vasodilation both in epicardial coronary and resistance vessels (Hambrecht et al., 2000). This relates to additional coronary benefits, such as amplified cardiac function, enriched endothelial function, and decreased blood clotting. This, in turn, can also lower blood pressure, decreasing one’s chance of a heart attack or stroke. By strengthening the heart through regular physical activity, it subsequently lowers the resting heart rate and increases the amount of blood pumped out of the heart with each beat. This enables the heart to work more efficiently and resultantly can lower one’s systolic blood pressure by “an average of 4 to 9 millimeters” (“Exercise: A drug-free approach to lowering high blood pressure – Mayo Clinic,” n.d.).

In terms of physical activity for the older population, exercise can be done with the goal of maintaining balance and improving flexibility. This can potentially decrease the risk of falling and reduce the risk of injuries, particularly fractures and broken bones, associated with the older population. For older women, Wolff et al. (1999) found that training program could prevent or reverse almost 1% of bone loss per year in the lumbar spine and femoral neck in both pre and post-menopausal women (Wolff et al., 1999). In terms of bone loss associated with aging, resistance exercise can also lead to increased bone mineral density, which therefore prevents the onset of osteoporosis (Warburton, Gledhill, & Quinney, 2001).

Osteoporosis, a common medical problem in the older population, is just one ‘disease’ that can be prevented through exercise. Through routine physical activity, the relative risk of developing colon cancer can be potentially reduced by 30-40% reduction, whilst the relative risk of developing breast cancer can potentially be reduced by 20-30% (Lee, 2003). This is through the reduction of the female hormone, estrogen. As women with high levels of estrogen have an increased risk of developing breast cancer, through reducing this hormone, the relative risk of developing breast cancer can be reduced (“Trim your cancer risk with exercise”). Exercise can also improve the quality of life following breast cancer diagnosis, through reducing fatigue and assisting with energy balance. Holmes et al. (2005) found that following the diagnosis of breast cancer, women who exercise moderately had improved survival rates compared with more sedentary women, who did not (Holmes et al., 2005).

Another great benefit of exercise is improved psychological well-being. This can be achieved through the effects of weight loss or through setting achievable goals and targets, of which people can gain confidence and improve their self-esteem, societal interaction, or simply through hormonal changes which reduce stress and anxiety. Smith et al (1996) suggests that the psychological benefits of exercise may equal or even surpass the physiological benefits. Likewise, Craft and Landers (1998) also discovered that exercise is as beneficial as psychotherapy and behavioral interventions (Craft & Landers, 1998). This is as a result of certain ‘feel-good brain chemicals’ called neurotransmitters, released during exercise, which cause increases in serum concentration of endogenous opioids, both beta endorphin and beta-lipotropic. These raised serum beta-endorphin levels cause many responses such as changes in mood state, ‘exercise-induced euphoria,’ pain perception, and altered stress responses of multiple hormones such as cortisol, growth hormone and ACTH (Harber & Sutton, 1984). These hormonal changes cause decreases in anxiety, depression and stress levels, and improvements in mood.

Exercise may also have a calming effect, as it increases body temperature, which may also reduce anxiety and stress, and thus improve psychological well-being. It also provides a setting in which social interaction can occur, and can provide a coping mechanism, or a form of distraction, for many people who are suffering from a variety of diseases and illnesses. With a Harvard Research Study, published in 2005, discovering that walking fast for around 35 minute per day, at least five times a week or for at least 60 minutes per day, three times a week, had a significant influence on mild to moderate depression symptoms (“Exercise and Depression – Harvard Health,” n.d.).

Improved psychological well-being can also lead to an improved overall quality of sleep, which is another benefit that can be obtained through regular exercise. Loprinzi & Cardinal (2011) found, from a nationally represented sample, that a 65% improvement in sleep quality can be obtained from 150 minutes of moderate to vigorous exercise a week. They also found that people found themselves to be less sleepy compared to individuals who did not exercise (Loprinzi & Cardinal, 2011). A research study, conducted by the Feinberg School of Medicine at Northwestern University, investigating the bi-directional relationship between school and exercise, found that following 16 weeks of routine exercise, exercise significantly improved sleep quality, as well as sleep duration and daytime sleepiness (Baron, Reid, & Zee, 2013).

This improved overall quality of sleep can also lead to improved cognitive performance (Colcombe and Kramer, 2003) as lack of sleep can lead to overworked neurons in the brain which can no longer function to coordinate information properly, thus impacting to ability to access information learned previously (“Sleep, Learning, and Memory | Healthy Sleep,”). Therefore alongside the effects of exercise, improved sleep quality can be extremely beneficial cognitively. As Erickson et al. (2011) found, aerobic exercise resulted in increased hippocampal volume in healthy community-dwelling older adults, which is significantly associated with enhanced levels of serum brain-derived neurotrophic factor and spatial performance. Which in other words, means that cognitive function is improved, and one’s learning ability is enhanced through exercise. Also when active individuals were compared to sedentary individuals, greater baseline levels of cortical activity were found in a study conducted by Dustman et al. (1990). The structure of the brain can also be changed through exercise. With Colcombe et al. (2006) using MRI scans to show that exercise amplifies brain volume, increasing the gray matter as well as white matter of the brain (Colcombe et al., 2006).

In terms of the volume and intensity of physical activity required to obtain these benefits, there is a dose-response relationship. The more exercise you do, the more benefits you will reap from it. The current American physical activity guidelines, recommended by the U.S. Department of Health and Human Services, are that adults require 150 minutes of moderate-intensity physical activity per week. It is also recommended that adults should engage in muscle-strengthening exercises for a minimum of 2 days per week. Youth, ages 6 to 17 years, are recommended as requiring 60 minutes of physical activity per day (“Appendix 1. Physical Activity Guidelines for Americans – 2015-2020 Dietary Guidelines – health.gov,” n.d.). Therefore, it is clear through the multitude of benefits available, that exercise is medicine, suitable for a large majority of the American population. From decreased risk of mortality, to reduced risk of cancer, to improved cognitive function, and greater quality of sleep, the benefits are endless! That is why I will be exercising for as long as I am physically able for the rest of my lifetime.

References

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Baron, K. G., Reid, K. J., & Zee, P. C. (2013). Exercise to Improve Sleep in Insomnia: Exploration of the Bidirectional Effects. Journal of Clinical Sleep Medicine.

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Craft, L. L., & Landers, D. M. (1998). The Effect of Exercise on Clinical Depression and Depression Resulting from Mental Illness: A Meta-Analysis. Journal of Sport and Exercise Psychology, 20(4), 339-357.

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