Why Should We Prioritize Exercise for More Than Just Musculoskeletal Health?

When someone is initially introduced to the concept of training at the gym or engaging in sports, their primary motivation often revolves around the desire to enhance their physical appearance. Some may even extend this reasoning to prioritize the improvement of their musculoskeletal health. However, it’s crucial to recognize that exercise offers benefits that extend far beyond aesthetics or isolated muscle enhancement. It should be regarded as a holistic approach to optimizing overall bodily function.

By carefully managing the intensity and timing of exercises, we can harness its potential to positively impact various systems within the body, fostering optimal well-being and functionality. Of particular concern is the current surge in inactivity, largely attributed to the transition from physically demanding occupations to sedentary lifestyles. This trend has propelled physical inactivity to become the fourth leading cause of death worldwide (1).

Today, there’s a notable shift towards a more inclusive approach to exercise, with tailored protocols emerging for different subsets of clinical populations. This evolution presents a fortunate opportunity for individuals within these groups to reap significant benefits. In this post, my aim is to delve into the primary effects that exercise exerts on the body. By breaking down these benefits in a clear and comprehensive manner, I hope to instill within you an intrinsic motivation to engage in training.

Nervous system

To encapsulate the extensive benefits of exercise on one of the most intricate systems, the nervous system, I propose delineating its effects on neurodegenerative processes, mental health, and pain management.

When discussing neurodegenerative diseases, such as Alzheimer’s and Parkinson’s, it’s crucial to explore how exercise can yield positive effects. Physical activity stimulates the release and synthesis of diverse neurotrophic factors, crucial for the survival of neurons impacted by degenerative processes (2). The two most extensively studied neurotrophic factors that exhibit increases with exercise are brain-derived neurotrophic factor (BDNF) and insulin-like growth factor (IGF-1) (3).

When examining mental health, individuals who engage in exercise consistently report better mental health functioning compared to those who do not (4). When focusing on the specific type of exercise, research indicates that aerobic exercises show superior efficacy in alleviating symptoms of depression and anxiety (5). Additionally, the treatment effect sizes observed with aerobic exercise are similar to those seen with conventional pharmacotherapeutic approaches (5).

Lastly, it has been discovered that physical inactivity is a risk factor for the development of pain (6). Regular physical activity helps manage pain by activating certain receptors in the nervous system (opioid receptors), which in turn reduce the activity of specific proteins involved in pain signaling, ultimately preventing heightened pain sensitivity (7).

Cardiovascular system

When considering the cardiovascular system, exercise emerges as a pivotal factor in promoting heart health. Understanding the mechanism behind this begins with recognizing the significance of cardiorespiratory fitness (CRF).

However, before delving into its relationship with cardiovascular health, it’s crucial to grasp how physical activity is measured. The most common unit of measurement used for this purpose is the metabolic equivalent (MET). 1 MET, refers to the resting metabolic rate, thus “the amount of oxygen consumed at rest, sitting quietly in a chair” (8). METs offer a convenient means of comparing the intensity of diverse activities and serve as a straightforward tool for evaluating an individual’s cardiorespiratory fitness level.

Even a modest improvement of just one MET in CRF has the potential to lower the risk of cardiovascular disease (CVD) by as much as 15% (9). Moreover, CRF naturally diminishes with age and is adversely affected by sedentary behavior. Studies have shown a positive correlation between sitting time and cardiovascular disease mortality (10).

Conversely, maintaining moderate to high CRF levels, typically defined as achieving 8 or more METs (with 8 METs representing the metabolic expenditure of jogging for the average individual), is linked to a decreased risk of CVD events (9).

Ultimately, regular physical activity is linked to a lower incidence of CVDs, improved vascular health, better lipid profiles and blood pressure, balanced autonomic function, and protection against heart injury during ischemia-reperfusion (11) .

Respiratory system

In 2006, the American Thoracic Society and European Respiratory Society jointly declared that engaging in active pulmonary rehabilitation can alleviate the negative symptoms experienced by individuals with chronic respiratory diseases (12). One of the primary complaints expressed by patients with this condition is dyspnea, characterized as “a subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity”(13). Hence, exercise should be undertaken cautiously but it must be performed, as muscle dysfunction can worsen exercise intolerance by amplifying pulmonary ventilation and triggering premature muscle fatigue. Enhancing skeletal muscle function can help alleviate symptoms by decreasing ventilatory demands and dynamic hyperinflation during exercise (14).

Inmune system

To illustrate this section, I want to highlight an example of a disease that significantly affects the immune system, namely cancer. Given the strong evidence that exercise enhances the well-being and survival of cancer patients, it is commonly used in conjunction to other treatments to fortify the inmune system, leading to a more potent therapeutic response (15). Muscles, being a significant secretory organ, release various proteins, known as myokines, that play crucial roles in regulating physiological processes, including immune function (16). Notably, myokines like IL-6, IL-7, and IL-15, released during exercise, support immune health by modulating the balance between pro-inflammatory and anti-inflammatory responses and promoting the maintenance of immune cell populations, suggesting a close interplay between muscle function and immune system regulation (17).

Lymphatic system

When there’s fluid overload, it’s often attributed to the lymphatic system, which causes progressive retention or redistribution of bodily fluids, hindering the functions of multiple body systems (18). Consequently, the lymphatic system plays a crucial role in regulating body fluids and contributes to the pathogenesis of cardiovascular diseases (19). Exercise, by stimulating muscle contraction and breathing, can boost lymphatic flow, potentially reducing fluid accumulation in tissues and interstitium (20). Studies demonstrate a substantial increase in lymph clearance rates during active exercise compared to resting levels (21).

Musculoskeletal system

And finally, let’s delve into the benefits of exercise on the musculoskeletal system, saving the big elephant in the room for last and completely flipping the iceberg upside down. When we consider the advantages of training, performance is not only exclusive to sports but also in everyday activities such as standing up, walking, and carrying objects. Through training, there are notable enhancements in various areas, including the rate of force development and power, improved jumping, sprinting and enhanced running economy (22,23,24).

Furthermore, studies have shown that strength training can reduce the risk of sports injuries by more than two-thirds and almost halve the occurrence of overuse injuries (25). In conclusion, strength training serves as a cornerstone treatment for age-related diseases like sarcopenia, which results in a decline in type 2 muscle fibers (fast twitch), and osteoporosis, which by providing mechanical loading, strength training can effectively reduce the risk of bone fractures (26, 27). Additionally, positive effects extend to other tissues within the musculoskeletal system, including improvements in cartilage and tendon properties (28, 29).

Final reflection

In essence, exercise transcends mere physical appearance or muscular enhancement. It constitutes a comprehensive approach to optimizing overall bodily function. By prudently managing exercise intensity and frequency, we can harness its potential to positively influence various physiological systems, fostering optimal well-being and functionality. The prevailing sedentary lifestyle epidemic underscores the imperative of prioritizing regular physical activity, especially given the emergence of tailored exercise protocols for diverse clinical populations.

From neuroprotection to cardiovascular health promotion and immune system modulation, exercise manifests multifaceted benefits. It stands as a potent intervention against age-related ailments, augments musculoskeletal health, and enhances overall quality of life. Thus, exercise embodies not merely a means to sculpt the body, but a fundamental cornerstone of holistic health and vitality, enriching every facet of our existence.

Bibliography

  1. Kohl HW 3rd, Craig CL, Lambert EV, Inoue S, Alkandari JR, Leetongin G, Kahlmeier S; Lancet Physical Activity Series Working Group. The pandemic of physical inactivity: global action for public health. Lancet. 2012 Jul 21;380(9838):294-305. doi: 10.1016/S0140-6736(12)60898-8.
  2. Ibáñez CF, Andressoo JO. Biology of GDNF and its receptors – Relevance for disorders of the central nervous system. Neurobiol Dis. 2017 Jan;97(Pt B):80-89. doi: 10.1016/j.nbd.2016.01.021.
  3. Deslandes A, Moraes H, Ferreira C, Veiga H, Silveira H, Mouta R, Pompeu FA, Coutinho ES, Laks J. Exercise and mental health: many reasons to move. Neuropsychobiology. 2009;59(4):191-8. doi: 10.1159/000223730.
  4. Chekroud SR, Gueorguieva R, Zheutlin AB, Paulus M, Krumholz HM, Krystal JH, Chekroud AM. Association between physical exercise and mental health in 1·2 million individuals in the USA between 2011 and 2015: a cross-sectional study. Lancet Psychiatry. 2018 Sep;5(9):739-746. doi: 10.1016/S2215-0366(18)30227-X.
  5. Kvam S, Kleppe CL, Nordhus IH, Hovland A. Exercise as a treatment for depression: A meta-analysis. J Affect Disord. 2016 Sep 15;202:67-86. doi: 10.1016/j.jad.2016.03.063.
  6. Landmark T, Romundstad PR, Borchgrevink PC, Kaasa S, Dale O. Longitudinal associations between exercise and pain in the general population–the HUNT pain study. PLoS One. 2013 Jun 12;8(6):e65279. doi: 10.1371/journal.pone.0065279.
  7. Sluka KA, Frey-Law L, Hoeger Bement M. Exercise-induced pain and analgesia? Underlying mechanisms and clinical translation. Pain. 2018 Sep;159 Suppl 1(Suppl 1):S91-S97. doi: 10.1097/j.pain.0000000000001235.
  8. Jetté M, Sidney K, Blümchen G. Metabolic equivalents (METS) in exercise testing, exercise prescription, and evaluation of functional capacity. Clin Cardiol. 1990 Aug;13(8):555-65. doi: 10.1002/clc.4960130809.
  9. Kodama S, Saito K, Tanaka S, Maki M, Yachi Y, Asumi M, Sugawara A, Totsuka K, Shimano H, Ohashi Y, Yamada N, Sone H. Cardiorespiratory fitness as a quantitative predictor of all-cause mortality and cardiovascular events in healthy men and women: a meta-analysis. JAMA. 2009 May 20;301(19):2024-35. doi: 10.1001/jama.2009.681.
  10. Kulinski JP, Khera A, Ayers CR, Das SR, de Lemos JA, Blair SN, Berry JD. Association between cardiorespiratory fitness and accelerometer-derived physical activity and sedentary time in the general population. Mayo Clin Proc. 2014 Aug;89(8):1063-71. doi: 10.1016/j.mayocp.2014.04.019.
  11. Fiuza-Luces C, Santos-Lozano A, Joyner M, Carrera-Bastos P, Picazo O, Zugaza JL, Izquierdo M, Ruilope LM, Lucia A. Exercise benefits in cardiovascular disease: beyond attenuation of traditional risk factors. Nat Rev Cardiol. 2018 Dec;15(12):731-743. doi: 10.1038/s41569-018-0065-1.
  12. Nici L, Donner C, Wouters E, Zuwallack R, Ambrosino N, Bourbeau J, Carone M, Celli B, Engelen M, Fahy B, Garvey C, Goldstein R, Gosselink R, Lareau S, MacIntyre N, Maltais F, Morgan M, O’Donnell D, Prefault C, Reardon J, Rochester C, Schols A, Singh S, Troosters T; ATS/ERS Pulmonary Rehabilitation Writing Committee. American Thoracic Society/European Respiratory Society statement on pulmonary rehabilitation. Am J Respir Crit Care Med. 2006 Jun 15;173(12):1390-413. doi: 10.1164/rccm.200508-1211ST.
  13. Parshall MB, Schwartzstein RM, Adams L, et al.. An official American Thoracic Society statement: update on the mechanisms, assessment, and management of dyspnea. Am J Respir Crit Care Med 2012; 185: 435–452. doi: 10.1164/rccm.201111-2042ST.
  14. Troosters T, Janssens W, Demeyer H, Rabinovich RA. Pulmonary rehabilitation and physical interventions. Eur Respir Rev. 2023 Jun 7;32(168):220222. doi: 10.1183/16000617.0222-2022.
  15. Lugo D, Pulido AL, Mihos CG, Issa O, Cusnir M, Horvath SA, Lin J, Santana O. The effects of physical activity on cancer prevention, treatment and prognosis: A review of the literature. Complement Ther Med. 2019 Jun;44:9-13. doi: 10.1016/j.ctim.2019.03.013.
  16. Pedersen BK, Febbraio MA. Muscles, exercise and obesity: skeletal muscle as a secretory organ. Nat Rev Endocrinol. 2012 Apr 3;8(8):457-65. doi: 10.1038/nrendo.2012.49.
  17. Pedersen BK, Febbraio MA. Muscle as an endocrine organ: focus on muscle-derived interleukin-6. Physiol Rev. 2008 Oct;88(4):1379-406. doi: 10.1152/physrev.90100.2007.
  18. Miller WL. Fluid Volume Overload and Congestion in Heart Failure: Time to Reconsider Pathophysiology and How Volume Is Assessed. Circ Heart Fail. 2016 Aug;9(8):e002922. doi: 10.1161/CIRCHEARTFAILURE.115.002922
  19. Klaourakis K, Vieira JM, Riley PR. The evolving cardiac lymphatic vasculature in development, repair and regeneration. Nat Rev Cardiol. 2021 May;18(5):368-379. doi: 10.1038/s41569-020-00489-x. Epub 2021 Jan 18.
  20. Lane K, Worsley D, McKenzie D. Exercise and the lymphatic system: implications for breast-cancer survivors. Sports Med. 2005;35(6):461-71. doi: 10.2165/00007256-200535060-00001.
  21. Havas E, Parviainen T, Vuorela J, Toivanen J, Nikula T, Vihko V. Lymph flow dynamics in exercising human skeletal muscle as detected by scintography. J Physiol. 1997 Oct 1;504 ( Pt 1)(Pt 1):233-9. doi: 10.1111/j.1469-7793.1997.233bf.x.
  22. Suchomel TJ, Nimphius S, Stone MH. The Importance of Muscular Strength in Athletic Performance. Sports Med. 2016 Oct;46(10):1419-49. doi: 10.1007/s40279-016-0486-0.
  23. Suchomel TJ, Nimphius S, Bellon CR, Stone MH. The Importance of Muscular Strength: Training Considerations. Sports Med. 2018 Apr;48(4):765-785. doi: 10.1007/s40279-018-0862-z.
  24. Støren O, Helgerud J, Støa EM, Hoff J. Maximal strength training improves running economy in distance runners. Med Sci Sports Exerc. 2008 Jun;40(6):1087-92. doi: 10.1249/MSS.0b013e318168da2f.
  25. Lauersen JB, Bertelsen DM, Andersen LB. The effectiveness of exercise interventions to prevent sports injuries: a systematic review and meta-analysis of randomised controlled trials. Br J Sports Med. 2014 Jun;48(11):871-7. doi: 10.1136/bjsports-2013-092538.
  26. Santilli V, Bernetti A, Mangone M, Paoloni M. Clinical definition of sarcopenia. Clin Cases Miner Bone Metab. 2014 Sep;11(3):177-80.
  27. Beck BR, Daly RM, Singh MA, Taaffe DR. Exercise and Sports Science Australia (ESSA) position statement on exercise prescription for the prevention and management of osteoporosis. J Sci Med Sport. 2017 May;20(5):438-445. doi: 10.1016/j.jsams.2016.10.001.
  28. Eckstein F, Hudelmaier M, Putz R. The effects of exercise on human articular cartilage. J Anat. 2006 Apr;208(4):491-512. doi: 10.1111/j.1469-7580.2006.00546.
  29. Docking SI, Cook J. How do tendons adapt? Going beyond tissue responses to understand positive adaptation and pathology development: A narrative review. J Musculoskelet Neuronal Interact. 2019 Sep 1;19(3):300-310.