By Hastings Lorman, Human Development

Author’s Note: This paper was written as a term paper for my HDE 117 class in which my professor, Dr. Carey, suggested that I submit this paper to the Aggie Transcript. Not only did I write this paper for my class, but I wrote it for myself as one of my goals while taking this class was to improve my writing skills. I chose to write on the effects of aerobic exercises on longevity because of my personal interest in successful aging and general health and well-being. The topic is similar to a previous term paper I wrote for HDE 100C which was The Effects of Aerobic Exercise on Executive Function. I earned a C+ on that paper and I saw this assignment as a redemption and a way to build my research and writing abilities. I hope that the reader is able to take away information on how to avoid or minimize the risk of chronic, degenerative diseases in adulthood. I also hope to introduce the reader to the concept of exercise as medicine.

ABSTRACT 

Physical health and cognition are determinants of mortality. These factors are also measurements to discern if aerobic exercise influences longevity. Aerobic exercise is a treatment that has been extensively studied and has been shown to have a positive effect on healthy aging and longevity, such as, lowering mortality in older age, improving VO2 uptake, and increasing lean body mass, which can facilitate greater physiological function in aging adults. Physical activity can ameliorate adverse symptoms resulting from cardiovascular diseases such as high blood pressure, diabetes, and stroke compounded by the presence of Alzheimer’s Disease. An active lifestyle has been linked to greater cognitive function and improved mood. Those who exercise have, on average, greater brain volume which can stall the deteriorating effects of neurological conditions to lengthen one’s life expectancy. The implementation of aerobic exercise and healthy lifestyle practices is a key factor contributing to overall successful aging and mitigating risk of morbidity [1].

Introduction 

Physical exercise is a highly effective and often prescribed treatment for a plethora of physical and mental health conditions. There is a strongly reviewed association between daily, moderate exercise and improved health, which becomes more imperative for successful aging. [2]. Healthy aging involves maintaining high function of physiological and cognitive abilities while resisting major diseases such as high blood pressure or Alzheimer’s disease [3]. One means of extending longevity in aging adults is a consistent aerobic exercise regimen such as brisk walking or jogging. By following a succinct, cardiovascular workout routine repeated multiple times a week, multimorbidity, the presence of two or more chronic illnesses, significantly improved. 

Procedure 

Table 1. The effectiveness of individualized aerobic exercise training combined with telephone-based motivational interviewing on physical activity amount based on mixed model analysis [4].

In a longitudinal study, designed to test an aerobic exercise treatment for aging adults, participants were found to have an increase of muscle protein synthesis leading to greater lean muscle and body mass. Physical exercise as a prophylactic was linked to combating frailty. Participants were selected for age and health condition [5]. Aging adults were defined as being 65 years or older and were most often suffering from pre-existing chronic conditions such as cardiovascular diseases and Alzheimer’s due to the subjects being residents of rehabilitation centers. Studies were also selected for individuals who did not already exercise on a regular schedule. 

 One-hundred fifty minutes of aerobic exercise a week is the recommended benchmark for healthy aging [6]. Physical exercises used as treatment were brisk walking and jogging, on a treadmill or outdoors, and cycle ergometer. Aerobic workouts were performed outdoors with weekly check-ins or completed in a lab or rehabilitation center. Aerobic exercise treatments were structured to be an hour long occurring 3-5 times a week for 12-18 weeks long. Physical and psychological measurements were taken before and after the training routine. 

Activities were recommended to either be intentional, such as exercises done with the purpose for gaining health benefits, or for leisure, such as walking to destress. Since lower muscle mass is associated with cancer-related disease, researchers paid attention to increases in muscle mass and VO2 uptake, which can determine brain function and metabolic health [7-8]. More vigorous exercises were allowed but subjects were encouraged to participate in moderate physical activities [9]. 

RESULTS 

Improved cardiovascular measures positively correlates with greater VO2 uptake, a leaner body mass (measured by BMI), and improved endurance in aerobic exercise [10]. Greater cognitive function is correlated to a decrease in depression after receiving an exercise treatment. Participants exhibited a decrease in high blood pressure, which is a predictor of chronic health conditions. Alzheimer’s patients after exercising on a weekly basis had greater brain volume. Aerobic exercise can help aging adults retain their autonomy in daily life by reducing the naturally occurring physiological stress that accompanies longevity.

Effects on Physical Health 

 Consistent aerobic exercise can improve different measures of health such as weight, energy and pre-existing conditions such as Type II diabetes and other cardiovascular diseases. Moderate aerobic exercise can have anti-inflammatory effects on the aging body and provide significant relief for chronic pain [11]. Exercises such as walking and jogging on a weekly basis contribute to an increase in peak oxygen consumption by 10 to 15 percent when targeting frailty, the physical and cognitive decline that develops with age [5]. Subjects who adhered to the exercise regimen were reported to have a lower BMI, a greater heart rate reserve, and a lower blood pressure reading after 12 weeks [4]. For people struggling with cardiovascular diseases such as Type II Diabetes, exercise can be used to help alleviate symptoms, produce healthier measures of fitness, and contribute to an increase in longevity [12].

Lack of physical exercise is linked to an increase in noncommunicable diseases such as diabetes and respiratory diseases. In addition, lack of physical exercise can increase hypertension and obesity. Twenty percent of deaths in the United States are due to obesity and Type II Diabetes [9]. The Copenhagen City Heart Study contributed additional evidence to the benefits that aerobic exercise can have on physical health and, in turn, life expectancy. The study concluded that those who are physically active have at least a 30 percent lower mortality risk when compared to inactive participants [13]. Non-joggers treated with an exercise regimen of light to moderate jogging had a significantly lower mortality rate than the sedentary control to prevent the accumulation of diseases that can contribute to high morbidity risk.

Aerobic activities can also improve the quality of life in aging adulthood. Capacity for movement and strength drastically decrease after 65 years, but the addition of aerobic activities in daily life can lead to better blood pressure and bone density [14]. This can help alleviate physical strain from activities of daily living [15]. Aerobic exercise is especially crucial for women, who, on average, experience a more drastic loss in bone density after twenty years. An active lifestyle should be prescribed as medicine and should be performed as a prophylactic and preservation of current ability. Along with reinforcing bone density in older age, aerobic exercise is also linked to retention of muscle mass [16]. As life becomes more sedentary for the aging population, health professionals urge aging populations to keep as mobile as possible. Short durations of exercise can help limit the physiological effects of aging and reduce the impact of chronic disease on activities of daily living [17].

Routine exercise can reduce the risk of many debilitating conditions that can become more prevalent at an older age, such as certain types of cancers and osteoporosis. Exercise benefits are directly linked to intensity and quantity of the workout. Aerobic exercise can also increase measures of fitness such as muscle tone, flexibility, and cardiorespiratory function. Oxygen carrying capacity decreases with age which correlates with a 5 to 10 percent decrease in physical ability. The risk of sarcopenia, a decline in muscle strength and volume, increases with age which is why physical fitness becomes more imperative for successful aging [18].

Effects on Cognition 

Aerobic exercise has led to improvements in memory processing and improvement in pre-existing neurological conditions such as Alzheimer’s Disease and dementia. The progression of Alzheimer’s Disease has been linked to a decrease in brain volume in the entorhinal cortex and hippocampus [19]. These brain regions are correlated with episodic memory which stores personal experiences of previous events [20]. Brisk walking on a regular basis significantly slows the growth of brain atrophy in Alzheimer’s, reducing the amount of nonfunctioning years of a patient’s lifespan.

Those with mild cognitive impairment are expected to live 3.5 years (male) and 4.1 years (female) after receiving a diagnosis. Aerobic exercise cannot stop the biological clock, an organism’s natural time and physiological cycle, nor can it reverse the effect of dementia. However, aerobic exercise can extend quality of life and extend the functioning years of those with memory diseases [27]. Biological age, the measurement of age based on biological health, is a more accurate predictor of mortality than chronological age [28]. Leukocyte telomere length, a biological age marker, appeared to be nine years healthier in active participants compared to sedentary ones [29]. Aerobic activities can compress the prevalence of symptoms in aging adults [18]. 

 Aerobic exercise is associated with activation of brain-derived neurotrophic factors (BDNF), promoted by the mild stress caused by physical activity. The exposure to mild stress with the purpose to build tolerance and improve cognitive function, known as the process of hormesis, is associated with greater neuroplasticity and thus successful aging [3]. Structural connectivity is not only correlated with better cognitive, overall operational processing, and executive function, working memory and self-regulation, but also with the prevention of Alzheimer’s and dementia. Exercise can help slow down the loss of gray matter and brain volume, contributing to greater longevity in those with degenerative conditions. 

As brain volume begins to decrease with age, moderate exercise has been shown to increase cortical thickness in preclinical Alzheimer patients. Decrease in brain volume is one of the most present symptoms of Alzheimer’s, and an active lifestyle could combat the progression of memory loss. Aerobic exercise specifically benefits homeostatic functions such as brain plasticity and neurogenesis [3]. Physical exercise can attenuate amyloid, an abnormal protein made in bone marrow, which can lead to greater cognition. The presence of amyloid beta proteins, an inactive part of the protein amyloid, is linked to memory diseases such as Alzheimer’s [22].

Risk of heart failure along with Alzheimer’s disease greatly increases with age due to rapid myocardial dysfunction and a higher rate of perfusion and inflammation. These risk factors can be worsened by cardiovascular diseases and can lead to cognitive impairment. The progression of Alzheimer’s is linked to a greater risk of stroke due to a buildup of amyloid beta proteins between brain cells. Cognitive decline is found in both conditions and is believed to be linked to the presence of amyloid beta protein build up to form plaque in the brain which affects myocardial function [23]. Likewise, heart disease is linked to the deposition of amyloid plaque into the heart which leads to swelling and stiffness of the soft tissue [24]. Exercise has been shown to improve some of the cognitive deficits brought upon by Alzheimer’s such as executive function. Cognitive test scores measuring memory, attention, and mood significantly improved after a physical exercise treatment consisting of cycling or psychomotor activities administered 2 to 6 times over the course of 7 weeks [25].

Exercise is significantly correlated to improvement in mood for people with memory conditions such as mild cognitive impairment and dementia. Adherence to an exercise regimen has decreased dependency on others for activities of daily living (ADL) along with increased mood and feelings of self-efficacy. Depression can cause both physiological and psychological stress leading to rapid degeneration due to worsening cognitive symptoms. Physical activity along with environmental enrichment can induce hippocampal neuro-genesis resulting in greater benefits than either physical activity or an enriched environment alone. Aerobic treatments stimulate neural pathways found in the hippocampus, an area of the brain that decreases in function in those with neurodegenerative diseases, leading to greater retention of cognitive operation [25].

Fig. 2. “Vicious circle” of inactivity and positive effects of regular physical activity [18].

Fig .3. The links between physical inactivity, abdominal adiposity, inflammation, and disease [11].

Fig. 4. Hypertension. A linear dose–response association exists between leisure-time physical activity (LTPA) and risk for hypertension [11].

Discussion 

Aerobic exercise should be prescribed to aging adults to preserve cognitive function with the purpose of extending longevity and improving quality of life. Exercises such as walking or jogging are non-invasive treatments that produce significant improvements in blood pressure, body mass, and cognition. Direct implementation of exercise is crucial for healthy aging and early intervention is associated with a lower risk of developing adult-onset diseases later in life [26]. Participants who have experienced many life stressors were able to find health benefits through routine exercise, especially when combined with other life pillars such as adequate nutrition, well-being, and sleep. Public health professionals and researchers encourage the public to use exercise as medicine [11]. There are currently no FDA-approved medications for functional decline [30]. Aerobic exercise is now being regarded as a lifestyle medicine to combat chronic diseases that can develop later in life.

The goal of aerobic exercise is compression morbidity which is reducing the number of years one is disabled and extending the ability to perform ADLs in older age. Successful aging consists of both biological and psychological measures. Causes of death have shifted from infectious diseases to age-related chronic diseases meaning that personal wellness and successful aging are becoming more salient with age. Absence of disease has appeared on surveys measuring feelings of content throughout aging and is a key factor in emotional wellness as well as physical [28].

Aerobic exercise should be done in consideration to the individual. Exercises performed should not negatively impact other physiological functions and can be uniquely designed for the individual’s ability. The CDC recommends 150 minutes per week such as 30 minutes of walking 5 times a week or 75 minutes of vigorous exercise per week such as running [31]. Aerobic exercise is prescribed as safe and doable for most individuals regardless of socioeconomic status or other sociological categories which makes it a more equitable treatment than pharmaceuticals or invasive surgeries. Aerobic exercises do have barriers that should be accounted for such as access to an appropriate location, lack of time, and disease-specific symptoms that infer with the ability to participate [4].

Conclusions 

The aging population of this generation is healthier than any previous cohort. To ensure the health of this generation and those to come, aerobic exercise must be incorporated into the weekly routine of the general population. It is important to consider exercise as medicine and as public health policy. With increasing longevity, older populations should place a greater focus on physical independence and the maintenance of well-being in old age. Social institutions, starting as early as primary school and as late as retirement home should encourage walking and light jogging for aging adults to maintain health and foster longevity. Education and encouragement to engage in practices that contribute to successful aging should be promoted to further ensure the health and longevity of future generations. Aerobic exercise is a crucial factor in healthy aging and elicits health benefits that decrease the likelihood of early morbidity.

References:

1. Friedman S. M. 2020. Lifestyle (Medicine) and Healthy Aging. Clinics in geriatric medicine, 36(4), 645–653. https://doi.org/10.1016/j.cger.2020.06.007
2. Carmona, J. J., & Michan, S. 2016. Biology of Healthy Aging and Longevity. Revista de investigacion clinica; organo del Hospital de Enfermedades de la Nutricion, 68(1), 7–16.
3. Urtamo, A., Jyväkorpi, S. K., & Strandberg, T. E. 2019. Definitions of successful aging: a brief review of a multidimensional concept. Acta bio-medica: Atenei Parmensis, 90(2), 359–363. https://doi.org/10.23750/abm.v90i2.8376
4. Lo, C.P., Chiang, S.L., Lin, C.H., Liu, H.C., Chiang, L.C. 2021. Effects of individualized aerobic exercise training on physical activity and health-related physical fitness among middle-aged and older adults with multimorbidity: a randomized controlled trial. Web of Science 18. 101. https://doi.org/10.3390/ijerph18010101
5. Aguirre, L.E., Villareal, D.T., 2015. Physical exercise as therapy for the frailty. Web of Science 83:83-92. https://doi.org/10.1159/000382065
6. Deslandes, A. 2013. The biological clock keeps ticking, but exercise may turn it back. Web of Science 71: 113-118. https://doi.org/10.1590/s0004-282×2013000200011
7. Caan, B. J., Cespedes Feliciano, E. M., & Kroenke, C. H. 2018. The Importance of Body Composition in Explaining the Overweight Paradox in Cancer-Counterpoint. Cancer research, 78(8), 1906–1912. https://doi.org/10.1158/0008-5472.CAN-17-3287
8. Flodin, P., Jonasson, L. S., Riklund, K., Nyberg, L., & Boraxbekk, C. J. 2017. Does Aerobic Exercise Influence Intrinsic Brain Activity? An Aerobic Exercise Intervention among Healthy Old Adults. Frontiers in aging neuroscience, 9, 267. https://doi.org/10.3389/fnagi.2017.00267
9. Pedersen, B. K. 2019. The physiology of optimizing health with a focus on exercise as medicine. Annual Review of Physiology 81:607-627. https://doi.org/10.1146/annurev-physiol-020518-114339
10. Kosh, G.L., Kemi, O.J., Qi, N., Leng, S.X., Bijma, H., Gilligan, L.J., Wilkinson, J.E., Wisloff, H., Hoydal, M.A., Rolim, N., Abadir, P.M., van Grevenhof, E.M, Smith, G.L., Burant, C.F., Ellingsen, O., Britton, S.L, Wisloff, U. 2011. Intrinsic aerobic capacity sets a divide for aging and longevity. Web of Science 109: 1162-U151. https://doi.org/10.1161/CIRCRESAHA.111.253807
11. Pedersen B. K. 2019. Which type of exercise keeps you young? Current opinion in clinical nutrition and metabolic care, 22(2), 167–173. https://doi.org/10.1097/MCO.0000000000000546
12. National Institute of Diabetes and Digestive and Kidney Diseases. 2016. Preventing Type II Diabetes. https://www.niddk.nih.gov/
13. Schnohr P, O’Keefe JH, Marott JL, Lange P, Jensen GB. 2015. Dose of jogging and long-term mortality: the Copenhagen City Heart Study. J Am Coll Cardiol. 10;65(5):411-9. https://doi.org/10.1016/j.jacc.2014.11.023
14. Pickering, C., & Kiely, J. 2018. ACTN3, Morbidity, and Healthy Aging. Frontiers in genetics, 9, 15. https://doi.org/10.3389/fgene.2018.00015
15. Fleg J. L. 2012. Aerobic exercise in the elderly: a key to successful aging. Discovery medicine, 13(70), 223–228. 
16. Crane, J. D., Macneil, L. G., & Tarnopolsky, M. A. 2013. Long-term aerobic exercise is associated with greater muscle strength throughout the lifespan. The journals of gerontology. Series A, Biological sciences, and medical sciences, 68(6), 631–638. https://doi.org/10.1093/gerona/gls237
17. American College of Sports Medicine, Chodzko-Zajko, W. J., Proctor, D. N., Fiatarone Singh, M. A., Minson, C. T., Nigg, C. R., Salem, G. J., & Skinner, J. S. 2009. American College of Sports Medicine position stand. Exercise and physical activity for older adults. Medicine and science in sports and exercise, 41(7), 1510–1530. https://doi.org/10.1249/MSS.0b013e3181a0c95c
18. Gremeaux, V., Gayda, M., Lepers, R., Sosner, P., Juneau, M., & Nigam, A. 2012. Exercise and longevity. Maturitas, 73(4),312–317.https://doi.org/10.1016/j.maturitas.2012.09.012
19. Scahill, R. I., Schott, J. M., Stevens, J. M., Rossor, M. N., & Fox, N. C. 2002. Mapping the evolution of regional atrophy in Alzheimer’s disease: unbiased analysis of fluid-registered serial MRI. Proceedings of the National Academy of Sciences of the United States of America, 99(7), 4703–4707.  https://doi.org/10.1073/pnas.052587399
20. Kitamura,T., Macdonald, C. J., & Tonegawa, S. 2015. Entorhinal-hippocampal neuronal circuits bridge temporally discontiguous events. Learning & memory, 22(9), 438–443.https://doi.org/10.1101/lm.038687.115

21. Um. Y. H., et al. 2020. Effects of Moderate Intensity Exercise on the Cortical Thickness and Subcortical Volumes of Preclinical Alzheimer’s Disease Patients: A Pilot Study. Psychiatry Investigation, 17(6), 613–619. https://doi.org/10.30773/pi.2020.0214
22. Chen, G. F., Xu, T. H., Yan, Y., Zhou, Y. R., Jiang, Y., Melcher, K., & Xu, H. E. 2017. Amyloid beta: structure, biology and structure-based therapeutic development. Acta pharmacologica Sinica, 38(9), 1205–1235. https://doi.org/10.1038/aps.2017.28
23. Troncone, L., Luciani, M., Coggins, M., Wilker, E. H., Ho, C. Y., Codispoti, K. E., Frosch, M. P., Kayed, R., & Del Monte, F. 2016. Aβ Amyloid Pathology Affects the Hearts of Patients with Alzheimer’s Disease: Mind the Heart. Journal of the American College of Cardiology, 68(22), 2395–2407. https://doi.org/10.1016/j.jacc.2016.08.073
24. Falk, R. H. 2020. Amyloid Heart Disease – Brigham and Women’s Hospital. Brigham and Women’s Hospital.
25. Karssemeijer, E., Aaronson, J. A., Bossers, W. J., Smits, T., Olde Rikkert, M., & Kessels, R. 2017. Positive effects of combined cognitive and physical exercise training on cognitive function in older adults with mild cognitive impairment or dementia: A meta-analysis. Ageing Research Reviews, 40,75–83. https://doi.org/10.1016/j.arr.2017.09.003
26. Colberg, S. R., Sigal, R. J., Fernhall, B., Regensteiner, J. G., Blissmer, B. J., Rubin, R. R., Chasan-Taber, L., Albright, A. L., Braun, B., American College of Sports Medicine, & American Diabetes Association 2010. Exercise and type 2 diabetes: the American College of Sports Medicine and the American Diabetes Association: Diabetes care, 33(12), e147–e167. https://doi.org/10.1249/MSS.0b013e3181eeb61c
27. Hale, J. M., Schneider, D. C., Mehta, N. K., & Myrskylä, M. 2020. Cognitive impairment in the U.S.: Lifetime risk, age at onset, and years impaired. SSM – population health, 11, 100577. https://doi.org/10.1016/j.ssmph.2020.100577
28. Depp, C., Vahia. V.I., Jeste, D., 2010.  Successful aging: Focus on cognitive and emotional health. Annual Review of Clinical Psychology. 6:527-550. https://doi.org/10.1146/annurev.clinpsy.121208.131449
29. Tucker L. A. 2017. Physical activity and telomere length in U.S. men and women: An NHANES investigation. Preventive medicine, 100, 145–151. https://doi.org/10.1016/j.ypmed.2017.04.027
30. Anton SD, Woods AJ, Ashizawa T, Barb D, Buford TW, Carter CS, Clark DJ, Cohen RA, Corbett DB, Cruz-Almeida Y, Dotson V, Ebner N, Efron PA, Fillingim RB, Foster TC, Gundermann DM, Joseph AM, Karabetian C, Leeuwenburgh C, Manini TM, Marsiske M, Mankowski RT, Mutchie HL, Perri MG, Ranka S, Rashidi P, Sandesara B, Scarpace PJ, Sibille KT, Solberg LM, Someya S, Uphold C, Wohlgemuth S, Wu SS, Pahor M. 2015. Successful aging: Advancing the science of physical independence in older adults. Ageing Res Rev. Pt B:304-27. https://doi.org/10.1016/j.arr.2015.09.005
31. Centers for Disease Control and Prevention 2020. How much physical activity do adults need? | Physical Activity. https://www.cdc.gov/physicalactivity/basics/adults/index.htm