This article is a correction to:
Exercise: A Protective Measure or an “Open Window” for COVID-19? A Mini Review
João B. Ferreira-Júnior
Eduardo D. S. Freitas
Suene F. N. Chaves- 1Federal Institute of Sudeste of Minas Gerais, Campus Rio Pomba, Rio Pomba, Brazil
- 2Neuromuscular Laboratory, Department of Health and Exercise Science, University of Oklahoma, Norman, OK, United States
- 3Department of Sports, Federal University of Minas Gerais, Belo Horizonte, Brazil
A Corrigendum on
Exercise: A Protective Measure or an “Open Window” for COVID-19? A Mini Review
by Ferreira-Júnior, J. B., Freitas, E. D. S., and Chaves, S. F. N. (2020). Front. Sports Act. Living 2:61. doi: 10.3389/fspor.2020.00061
In the original article, the reference for Chen et al. (2020) was incorrectly written as Chen, P., Mao, L., Nassis, G. P., Harmer, P., Ainsworth, B. E., and Li, F. (2020). Wuhan coronavirus (2019-nCoV): the need to maintain regular physical activity while taking precautions. J. Sport Heal. Sci. 9, 103–104. doi: 10.1016/j.jshs.2020.02.001. It should be Chen, P., Mao, L., Nassis, G. P., Harmer, P., Ainsworth, B. E., and Li, F. (2020). Coronavirus disease (COVID-19): The need to maintain regular physical activity while taking precautions. J. Sport Health. Sci. 9, 103–104. doi: 10.1016/j.jshs.2020.02.001.
In the original article (Flynn et al., 1999) was not cited or it was replaced by Fahlman et al. (2000). The citation has now been inserted in the section Can Training Status Protect Against COVID-19 Infection?. Paragraph five should read:
The contradictions displayed across the studies discussed above may be related to differences in the immune response to training status (more trained vs. less trained individuals). Some studies have reported reductions in the lymphocyte proliferative response (Papa et al., 1989) and suppressed neutrophil function (Lewicki et al., 1988; Baj et al., 1994), whereas other studies have shown no alteration in either lymphocyte or neutrophil status after a period of exercise (Tvede et al., 1991; Flynn et al., 1999; Ferrari et al., 2013), or even increases (Brunelli et al., 2014) when comparing different training statuses.
In addition, the citation has now been inserted in the section Can an Acute Exercise Session Increase the Risks for Covid-19 Infection?
Paragraph two
Several studies have investigated the effects of a single exercise session on immune function by measuring acute changes in various parameters (Flynn et al., 1999; Fahlman et al., 2000; Steensberg et al., 2001; Kakanis et al., 2010). However, few studies have utilized resistance exercise protocols (Nieman et al., 1995; Flynn et al., 1999) or home-based exercises, those likely to be performed during the current pandemic which most likely consist of adapted forms of resistance exercise.
Paragraph three
Nieman et al. (1995) had participants perform multiple sets of squat exercise to failure at 65% of one-maximum repetition (1-RM) and observed conflicting results with leukocytes counts increasing immediately post-exercise and remaining elevated up to 2 h after, whereas lymphocytes number increased post-exercise but decreased below baseline levels 2 h post-exercise. Nonetheless, it is important to note that Nieman et al. (1995) utilized a sample of 10 resistance trained individuals with a mean age of ~25 years, however, COVID-19 is particularly dangerous to older individuals, which represents most of the COVID-19-related deaths reported to date (Verity et al., 2020). Therefore, it is important to consider the potential immunosuppressive effects of resistance exercise for elderly participants. In this regard, Flynn et al. (1999) investigated the acute effects of a resistance exercise session performed at 80% 1-RM on several immune function parameters in women aged 67 and 84 years and reported no suppression of immune function during the recovery period from the exercise bout. Finally, it is important to highlight that URTI incidences were not assessed in any of these studies.
Paragraph five
The different results across these studies may be due to the variability in the immune system responses to an acute exercise session. Although a number of studies have observed an immunosuppressive response after prolonged and intense exercise bouts (Steensberg et al., 2001; Kakanis et al., 2010), no changes in immune function have also been observed (Flynn et al., 1999).
In the original article, there was an error. Incorrect references were cited.
A correction has been made to the section Can Training Status Protect Against Covid-19 Infection?, paragraph three:
On the other hand, other studies have shown no protective effects of exercise training programs on URTI incidences (Nieman et al., 1990; Kostka and Praczko, 2007; Kostka et al., 2008; Walsh et al., 2011). To illustrate, a study with obese sedentary women who completed 15 weeks of endurance training (walking at 60% heart rate reserve), five times a week, reported no differences in the number of URTI in comparison to the untrained control subjects (Nieman et al., 1990). However, the number of days with URTI symptoms was lower in the exercise group in comparison to the control group, which was confirmed by additional studies (Kostka and Praczko, 2007; Kostka et al., 2008; Walsh et al., 2011). An additional study did not find any relationship between perceived physical fitness levels and URTI incidences (Kostka et al., 2008).
The authors apologize for these errors and state that this does not change the scientific conclusions of the article in any way. The original article has been updated.
References
Baj, Z., Kantorski, J., Majewska, E., Zeman, K., Pokoca, L., Fornalczy, E., et al. (1994). Immunological status of competitive cyclists before and after the training season. Int. J. Sports Med. 15, 319–324. doi: 10.1055/s-2007-1021067
Brunelli, D. T., Rodrigues, A., Lopes, W. A., Gáspari, A. F., Bonganha, V., Montagner, P. C., et al. (2014). Monitoring of immunological parameters in adolescent basketball athletes during and after a sports season. J. Sports Sci. 32, 1050–1059. doi: 10.1080/02640414.2013.878806
Chen, P., Mao, L., Nassis, G. P., Harmer, P., Ainsworth, B. E., and Li, F. (2020). Coronavirus disease (COVID-19): The need to maintain regular physical activity while taking precautions. J. Sport Health. Sci. 9, 103–104. doi: 10.1016/j.jshs.2020.02.001
Fahlman, M. M., Boardley, D., Flynn, M. G., Braun, W. A., Lambert, C. P., and Bouillon, L. E. (2000). Effects of endurance training on selected parameters of immune function in elderly women. Gerontology 46, 97–104. doi: 10.1159/000022142
Ferrari, H. G., Gobatto, C. A., and Manchado-Gobatto, F. B. (2013). Training load, immune system, upper respiratory symptoms and performance in well-trained cyclists throughout a competitive season. Biol. Sport 30, 289–294. doi: 10.5604/20831862.1077555
Flynn, M. G., Fahlman, M., Braun, W. A., Lambert, C. P., Bouillon, L. E., Brolinson, P. G., et al. (1999). Effects of resistance training on selected indexes of immune function in elderly women. J. Appl. Physiol. 86, 1905–1913. doi: 10.1152/jappl.1999.86.6.1905
Kakanis, M., Peake, J., Hooper, S., Gray, B., and Marshall-Gradisnik, S. (2010). The open window of susceptibility to infection after acute exercise in healthy young male elite athletes. J. Sci. Med. Sport 13, e84–e85. doi: 10.1016/j.jsams.2010.10.640
Kostka, T., Drygas, W., Jegier, A., and Praczko, K. (2008). Physical activity and upper respiratory tract infections. Int. J. Sports Med. 29, 158–162. doi: 10.1055/s-2007-965806
Kostka, T., and Praczko, K. (2007). Interrelationship between physical activity, symptomatology of upper respiratory tract infections, and depression in elderly people. Gerontology 53, 187–193. doi: 10.1159/000100017
Lewicki, R., Tchorzewski, H., Majewska, E., Nowak, Z., and Baj, Z. (1988). Effect of maximal physical exercise on T-lymphocyte subpopulations and on interleukin 1 (IL 1) and interleukin 2 (IL 2) production in vitro. Int. J. Sports Med. 9, 114–117. doi: 10.1055/s-2007-1024990
Nieman, D. C., Henson, D. A., Sampson, C. S., Herring, J. L., Suttles, J., Conley, M., et al. (1995). The acute immune response to exhaustive resistance exercise. Int. J. Sports Med. 16, 322–328. doi: 10.1055/s-2007-973013
Nieman, D. C., Nehlsen-Cannarella, S. L., Markoff, P. A., Balk-Lamberton, A. J., Yang, H., Chritton, D. B. W., et al. (1990). The effects of moderate exercise training on natural killer cells and acute upper respiratory tract infections. Int. J. Sports Med. 11, 467–473. doi: 10.1055/s-2007-1024839
Papa, S., Vitale, M., Mazzotti, G., Neri, L. M., Monti, G., and Manzoli, F. A. (1989). Impaired lymphocyte stimulation induced by long-term training. Immunol. Lett. 22, 29–33. doi: 10.1016/0165-2478(89)90138-7
Steensberg, A., Toft, A. D., Bruunsgaard, H., Sandmand, M., Halkjær-Kristensen, J., and Pedersen, B. K. (2001). Strenuous exercise decreases the percentage of type 1 T cells in the circulation. J. Appl. Physiol. 91, 1708–1712. doi: 10.1152/jappl.2001.91.4.1708
Tvede, N., Steensberg, J., Baslund, B., Halkjær-Kristensen, J., and Pedersen, B. K. (1991). Cellular immunity in highly trained elite racing cyclists during periods of training with high and low intensity. Scand. J. Med. Sci. Sports 1, 163–166. doi: 10.1111/j.1600-0838.1991.tb00290.x
Verity, R., Okell, L. C., Dorigatti, I., Winskill, P., Whittaker, C., Imai, N., et al. (2020). Estimates of the severity of coronavirus disease 2019 : a model-based analysis. Lancet Infect. Dis. 3099, 1–9. doi: 10.1016/S1473-3099(20)30243-7
Keywords: coronavirus, immune system, endurance training, resistance training, blood flow restriction, no load resistance training
Citation: Ferreira-Júnior JB, Freitas EDS and Chaves SFN (2020) Corrigendum: Exercise: A Protective Measure or an “Open Window” for COVID-19? A Mini Review. Front. Sports Act. Living 2:101. doi: 10.3389/fspor.2020.00101
Received: 10 June 2020; Accepted: 30 June 2020;
Published: 14 August 2020.
Edited and reviewed by: Jun Sugawara, National Institute of Advanced Industrial Science and Technology (AIST), Japan
Copyright © 2020 Ferreira-Júnior, Freitas and Chaves. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: João B. Ferreira-Júnior, jbfjunior@gmail.com