Exercise during the coronavirus pandemic, two sides of the same coin: the intensity-specific effect of physical training on the innate and acquired immune systems of humans

Document Type : Review

Authors

1 Department of Exercise Physiology, Faculty of Sports Sciences, University of Mazandaran, Babolsar, Mazandaran, Iran

2 Assistant Professor of Exercise Physiology, Clinical Biomechanics and Ergonomics Center, Aja University of Medical Sciences, Tehran, Iran

3 Department of Exercise physiology, Ahvaz Branch, Islamic Azad university, Ahvaz, Iran

4 Ph.D. in Sport Management, Islamic Azad University, Tehran North branch, Tehran, Iran

Abstract

In recent years, the global spread of the novel coronavirus responsible for COVID-19 has posed an unprecedented public health threat. Fortunately, research has shown that regular, moderate-intensity aerobic exercise can have a positive impact on the immune system when it comes to upper respiratory tract infections (URTI). Numerous studies have demonstrated that moderate aerobic exercise at 65–80% VO2max can boost antibody production, lymphocyte proliferation, gamma interferon levels, immunoglobulin M and G levels, natural killer cell counts, and Toll-like receptor activity. This suggests that exercise is beneficial for immune function in both recreational and elite athletes, with a J-shaped curve for recreational athletes and an S-shaped curve for elite athletes. Therefore, it's important for individuals of all ages to engage in regular exercise to enhance their immune response. Some helpful recommendations may include: During this time, it's wise to avoid heavy exercise, as it could potentially increase susceptibility to infection through the open window hypothesis. However, healthy individuals who don't exhibit symptoms can still benefit from moderate exercise while following proper hygiene protocols. This aligns with the J-shaped model, which suggests that moderate exercise can enhance immune system function. If you're experiencing mild upper respiratory symptoms, such as a runny nose or sinus congestion, it's safe to engage in light exercise for no more than 60 minutes with precautions. However, it's important to limit the intensity and duration to no more than 60% VO2max in one hour. If you're exhibiting lower-neck symptoms, such as fever, cough, severe sore throat, myalgia, shortness of breath, or general fatigue, it's best to avoid exercise altogether if you suspect you may have COVID-19.

Keywords


  1. Wertheim JO, Chu DK, Peiris JS, Kosakovsky Pond SL, Poon LL. A case for the ancient origin of coronaviruses. J Virol. 2013; 87 (12):7039-45. doi:10.1128/JVI.03273-12 PMid:23596293 PMCid:PMC3676139
  2. World Health Organization. Laboratory testing of human suspected cases of novel coronavirus (nCoV) infection: interim guidance, 10 January 2020. World Health Organization; 2020.
  3. Casanova LM, Jeon S, Rutala WA, Weber DJ, Sobsey MD. Effects of air temperature and relative humidity on coronavirus survival on surfaces. Appl Environ Microbiol. 2010;76(9):2712-7. doi:10.1128/AEM.02291-09 PMid:20228108 PMCid:PMC2863430
  4. Manson JE, Greenland P, LaCroix AZ, Stefanick ML, Mouton CP, Oberman A, Perri MG, Sheps DS, Pettinger MB, Siscovick DS. Walking compared with vigorous exercise for the prevention of cardiovascular events in women. N Engl J Med. 2002;347(10):716-25. doi:10.1056/NEJMoa021067 PMid:12213942
  5. Nieman DC, Nehlsen-Cannarella SL. The immune response to exercise. Semin Hematol. 1994; 31(2): 166-179.
  6. Lowder T, Padgett DA, Woods JA. Moderate exercise protects mice from death due to influenza virus. Brain Behav Immun. 2005; 19(5):377-80. doi:10.1016/j.bbi.2005.04.002 PMid:15922557
  7. Brown AS, Davis JM, Murphy EA, Carmichael MD, Ghaffar A, Mayer EP. Gender differences in viral infection after repeated exercise stress. Med Sci Sports Exerc. 2004; 36(8):1290-5. doi:10.1249/01.MSS.0000135798.72735.B3 PMid:15292734
  8. Wong CM, Lai HK, Ou CQ, Ho SY, Chan KP, Thach TQ, Yang L, Chau YK, Lam TH, Hedley AJ, Peiris JS. Is exercise protective against influenza-associated mortality?. PloS one. 2008;3(5):e2108.
  9. Woods JA, Keylock KT, Lowder T, Vieira VJ, Zelkovich W, Dumich S, Colantuano K, Lyons K, Leifheit K, Cook M, Chapman‐Novakofski K. Cardiovascular exercise training extends influenza vaccine seroprotection in sedentary older adults: the immune function intervention trial. J Am Geriatr Soc. 2009; 57 (12):2183-91. doi:10.1111/j.1532-5415.2009.02563.x PMid:20121985
  10. Williams PT. Reduced total and cause-specific mortality from walking and running in diabetes. Med Sci Sports Exerc. 2014;46 (5):933. doi:10.1249/MSS.0000000000000176 PMid:24968127 PMCid:PMC4157907
  11. Williams PT. Dose-response relationship between exercise and respiratory disease mortality. Med Sci Sports Exerc. 2014;46 (4): 711. doi:10.1249/MSS.0000000000000142 PMid:24002349 PMCid:PMC4073613
  12. Kohut ML, Sim YJ, Yu S, Yoon KJ, Loiacono CM. Chronic exercise reduces illness severity, decreases viral load, and results in greater anti-inflammatory effects than acute exercise during influenza infection. J Infect Dis. 2009;200 (9):1434-42. doi:10.1086/606014 PMid:19811098 PMCid:PMC2812897
  13. Warren KJ, Olson MM, Thompson NJ, Cahill ML, Wyatt TA, Yoon KJ, Loiacono CM, Kohut ML. Exercise improves host response to influenza viral infection in obese and non-obese mice through different mechanisms. PloS one. 2015;10(6):e0129713.
  14. Folsom R, Littlefield‐Chabaud MA, French DD, Pourciau SS, Mistric L, Horohov DW. Exercise alters the immune response to equine influenza virus and increases susceptibility to infection. Equine Vet J. 2001;33(7):664-9. doi:10.2746/042516401776249417 PMid:11770987
  15. Kohut ML, Arntson BA, Lee W, Rozeboom K, Yoon KJ, Cunnick JE, McElhaney J. Moderate exercise improves antibody response to influenza immunization in older adults. Vaccine. 2004;22(17-18):2298-306. doi:10.1016/j.vaccine.2003.11.023 PMid:15149789
  16. de Araújo AL, Silva LC, Fernandes JR, Matias MD, Boas LS, Machado CM, Garcez-Leme LE, Benard G. Elderly men with moderate and intense training lifestyle present sustained higher antibody responses to influenza vaccine. Age. 2015;37(6):1-8. doi:10.1007/s11357-015-9843-4 PMid:26480853 PMCid:PMC5005841
  17. Zhu W. Should, and how can, exercise be done during a coronavirus outbreak? An interview with Dr. Jeffrey A. Woods. J Sport Health Sci. 2020;9(2):105. doi:10.1016/j.jshs.2020.01.005 PMid:32099717 PMCid:PMC7031769
  18. Nieman DC, Wentz LM. The compelling link between physical activity and the body's defense system. J Sport Health Sci. 2019;8 (3):201-17. doi:10.1016/j.jshs.2018.09.009 PMid:31193280 PMCid:PMC6523821
  19. Dimitrov S, Hulteng E, Hong S. Inflammation and exercise: Inhibition of monocytic intracellular TNF production by acute exercise via β2-adrenergic activation. Brain Behav Immun. 2017; 61:60-8. doi:10.1016/j.bbi.2016.12.017 PMid:28011264 PMCid:PMC6555138
  20. Campbell JP, Turner JE. Debunking the myth of exercise-induced immune suppression: redefining the impact of exercise on immunological health across the lifespan. Front Immunol. 2018: 648. doi:10.3389/fimmu.2018.00648 PMid:29713319 PMCid:PMC5911985
  21. Yang Y, Verkuilen J, Rosengren KS, Mariani RA, Reed M, Grubisich SA, Woods JA. Effects of a Taiji and Qigong intervention on the antibody response to influenza vaccine in older adults. Am J Chin Med. 2007;35(04):597-607. doi:10.1142/S0192415X07005090 PMid:17708626
  22. Falkenberg RI, Eising C, Peters ML. Yoga and immune system functioning: a systematic review of randomized controlled trials. J Behav Med. 2018;41(4):467-82. doi:10.1007/s10865-018-9914-y PMid:29429046
  23. Martin SA, Pence BD, Woods JA. Exercise and respiratory tract viral infections. Exerc Sport Sci Rev. 2009;37(4):157. doi:10.1097/JES.0b013e3181b7b57b PMid:19955864 PMCid:PMC2803113
  24. Shirvani H, Rostamkhani F. Exercise considerations during coronavirus disease 2019 (COVID-19) Outbreak: A narrative review. J Mil Med. 2020;22(2):161-8.