{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,10]],"date-time":"2026-06-10T15:41:50Z","timestamp":1781106110420,"version":"3.54.1"},"reference-count":46,"publisher":"National Academy of Sciences","issue":"9","license":[{"start":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T00:00:00Z","timestamp":1676937600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001659","name":"Deutsche Forschungsgemeinschaft","doi-asserted-by":"publisher","award":["KA1808\/37-1"],"award-info":[{"award-number":["KA1808\/37-1"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007323","name":"Bundesinstitut f\u00fcr Sportwissenschaft","doi-asserted-by":"publisher","award":["ZMVI4-070115\/20-21"],"award-info":[{"award-number":["ZMVI4-070115\/20-21"]}],"id":[{"id":"10.13039\/501100007323","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.pnas.org"],"crossmark-restriction":true},"short-container-title":["Proc. Natl. Acad. Sci. U.S.A."],"published-print":{"date-parts":[[2023,2,28]]},"abstract":"<jats:p>Pathogens such as severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), influenza, and rhinoviruses are transmitted by airborne aerosol respiratory particles that are exhaled by infectious subjects. We have previously reported that the emission of aerosol particles increases on average 132-fold from rest to maximal endurance exercise. The aims of this study are to first measure aerosol particle emission during an isokinetic resistance exercise at 80% of the maximal voluntary contraction until exhaustion, second to compare aerosol particle emission during a typical spinning class session versus a three-set resistance training session. Finally, we then used this data to calculate the risk of infection during endurance and resistance exercise sessions with different mitigation strategies. During a set of isokinetic resistance exercise, aerosol particle emission increased 10-fold from 5,400 \u00b1 1,200 particles\/min at rest to 59,000 \u00b1 69,900 particles\/min during a set of resistance exercise. We found that aerosol particle emission per minute is on average 4.9-times lower during a resistance training session than during a spinning class. Using this data, we determined that the simulated infection risk increase during an endurance exercise session was sixfold higher than during a resistance exercise session when assuming one infected participant in the class. Collectively, this data helps to select mitigation measures for indoor resistance and endurance exercise classes at times where the risk of aerosol-transmitted infectious disease with severe outcomes is high.<\/jats:p>","DOI":"10.1073\/pnas.2220882120","type":"journal-article","created":{"date-parts":[[2023,2,21]],"date-time":"2023-02-21T13:58:31Z","timestamp":1676987911000},"update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":9,"title":["Respiratory aerosol particle emission and simulated infection risk is greater during indoor endurance than resistance exercise"],"prefix":"10.1073","volume":"120","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5041-0284","authenticated-orcid":false,"given":"Benedikt","family":"Schumm","sequence":"first","affiliation":[{"name":"Institute of Fluid Mechanics and Aerodynamics, Universit\u00e4t der Bundeswehr M\u00fcnchen, 85577 Neubiberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9224-6029","authenticated-orcid":false,"given":"Marie","family":"Heiber","sequence":"additional","affiliation":[{"name":"Institute of Sport Science, Universit\u00e4t der Bundeswehr M\u00fcnchen, 85577 Neubiberg, Germany"},{"name":"Associate Professorship of Exercise Biology, Technische Universit\u00e4t M\u00fcnchen, 80809 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6457-9280","authenticated-orcid":false,"given":"Felix","family":"Gr\u00e4tz","sequence":"additional","affiliation":[{"name":"Associate Professorship of Exercise Biology, Technische Universit\u00e4t M\u00fcnchen, 80809 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luca","family":"Stabile","sequence":"additional","affiliation":[{"name":"University of Cassino and Southern Lazio, Department of Civil and Mechanical Engineering, 03043 Cassino, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Giorgio","family":"Buonanno","sequence":"additional","affiliation":[{"name":"University of Cassino and Southern Lazio, Department of Civil and Mechanical Engineering, 03043 Cassino, Italy"},{"name":"Queensland University of Technology, 4000 QLD, Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3003-3378","authenticated-orcid":false,"given":"Martin","family":"Sch\u00f6nfelder","sequence":"additional","affiliation":[{"name":"Associate Professorship of Exercise Biology, Technische Universit\u00e4t M\u00fcnchen, 80809 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2614-5374","authenticated-orcid":false,"given":"Rainer","family":"Hain","sequence":"additional","affiliation":[{"name":"Institute of Fluid Mechanics and Aerodynamics, Universit\u00e4t der Bundeswehr M\u00fcnchen, 85577 Neubiberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian J.","family":"K\u00e4hler","sequence":"additional","affiliation":[{"name":"Institute of Fluid Mechanics and Aerodynamics, Universit\u00e4t der Bundeswehr M\u00fcnchen, 85577 Neubiberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Henning","family":"Wackerhage","sequence":"additional","affiliation":[{"name":"Associate Professorship of Exercise Biology, Technische Universit\u00e4t M\u00fcnchen, 80809 Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[2023,2,21]]},"reference":[{"key":"e_1_3_4_1_2","doi-asserted-by":"crossref","unstructured":"H. Loe S. Steinshamn U. Wisl\u00f8ff Cardio-respiratory reference data in 4631 healthy men and women 20\u201390 years: The HUNT 3 fitness study. PLoS One 9 e113884 (2014) 10.1371\/journal.pone.0113884. e113884","DOI":"10.1371\/journal.pone.0113884"},{"key":"e_1_3_4_2_2","doi-asserted-by":"crossref","unstructured":"J. M. Clark F. C. Hagerman R. Gelfand Breathing patterns during submaximal and maximal exercise in elite oarsmen. J. Appl. Physiol. Respir. Environ. Exerc. Physiol. 55 440\u2013446 (1983) 10.1152\/jappl.1983.55.2.440.","DOI":"10.1152\/jappl.1983.55.2.440"},{"key":"e_1_3_4_3_2","doi-asserted-by":"crossref","unstructured":"B. Mutsch Aerosol particle emission increases exponentially above moderate exercise intensity resulting in superemission during maximal exercise. Proc. Natl. Acad. Sci. U.S.A. 119 e2202521119 (2022) 10.1073\/pnas.2202521119. e2202521119","DOI":"10.1073\/pnas.2202521119"},{"key":"e_1_3_4_4_2","doi-asserted-by":"crossref","unstructured":"M. Valtonen Increased risk of respiratory viral infections in elite athletes: A controlled study. PLoS One 16 e0250907 (2021) 10.1371\/journal.pone.0250907. e0250907","DOI":"10.1371\/journal.pone.0250907"},{"key":"e_1_3_4_5_2","unstructured":"Z. Peng Practical indicators for risk of airborne transmission in shared indoor environments and their application to COVID-19 outbreaks. Environ. Sci. Technol. 56 1125\u20131137 (2022) 10.1021\/acs.est.1c06531."},{"key":"e_1_3_4_6_2","unstructured":"J. Medeiros The science behind Chris Froome and Team Sky's tour de France preparations. https:\/\/www.wired.co.uk\/article\/tour-de-france-science-behind-team-sky. Accessed 30 January 2023.)."},{"key":"e_1_3_4_7_2","unstructured":"Imperial College London. EIS and collaborators aim to reduce the impact of respiratory illness on athletes' training and competition availability. https:\/\/eis2win.co.uk\/article\/eis-and-collaborators-aim-to-reduce-the-impact-of-respiratory-illness-on-athletes-training-and-competition-availability\/. Accessed 30 January 2023.)."},{"key":"e_1_3_4_8_2","unstructured":"A. Gupta Extrapulmonary manifestations of COVID-19. Nat. Med. 26 1017\u20131032 (2020) 10.1038\/s41591-020-0968-3."},{"key":"e_1_3_4_9_2","doi-asserted-by":"publisher","DOI":"10.3389\/fphys.2021.593223"},{"key":"e_1_3_4_10_2","doi-asserted-by":"crossref","unstructured":"M. Halle Exercise and sports after COVID-19-Guidance from a clinical perspective. Transl. Sports Med. 4 310\u2013318 (2021) 10.1002\/tsm2.247.","DOI":"10.1002\/tsm2.247"},{"key":"e_1_3_4_11_2","doi-asserted-by":"crossref","unstructured":"P. Schellhorn K. Klingel C. Burgstahler Return to sports after COVID-19 infection. Eur. Heart J. 41 4382\u20134384 (2020) 10.1093\/eurheartj\/ehaa448.","DOI":"10.1093\/eurheartj\/ehaa448"},{"key":"e_1_3_4_12_2","doi-asserted-by":"crossref","unstructured":"A. N. Kochi A. P. Tagliari G. B. Forleo G. M. Fassini C. Tondo Cardiac and arrhythmic complications in patients with COVID-19. J. Cardiovasc. Electrophysiol. 31 1003\u20131008 (2020) 10.1111\/jce.14479.","DOI":"10.1111\/jce.14479"},{"key":"e_1_3_4_13_2","doi-asserted-by":"crossref","unstructured":"B. J. Maron J. J. Doerer T. S. Haas D. M. Tierney F. O. Mueller Sudden deaths in young competitive athletes: Analysis of 1866 deaths in the United States 1980\u20132006. Circulation 119 1085\u20131092 (2009) 10.1161\/CIRCULATIONAHA.108.804617.","DOI":"10.1161\/CIRCULATIONAHA.108.804617"},{"key":"e_1_3_4_14_2","doi-asserted-by":"crossref","unstructured":"T. Byers COVID-19 impacts on sport governance and management: A global critical realist perspective. Managing Sport and Leisure 27 99\u2013107 (2022) 10.1080\/23750472.2020.1867002.","DOI":"10.1080\/23750472.2020.1867002"},{"key":"e_1_3_4_15_2","doi-asserted-by":"crossref","unstructured":"F. C. Bull World Health Organization 2020 guidelines on physical activity and sedentary behaviour. Br. J. Sports Med. 54 1451\u20131462 (2020) 10.1136\/bjsports-2020-102955.","DOI":"10.1136\/bjsports-2020-102955"},{"key":"e_1_3_4_16_2","doi-asserted-by":"crossref","unstructured":"A. F. Vallejo E. T. Schroeder L. Zheng N. E. Jensky F. R. Sattler Cardiopulmonary responses to eccentric and concentric resistance exercise in older adults. Age Ageing. 35 291\u2013297 (2006) 10.1093\/ageing\/afj082.","DOI":"10.1093\/ageing\/afj082"},{"key":"e_1_3_4_17_2","doi-asserted-by":"crossref","unstructured":"D. A. Hackett C.-M. Chow The Valsalva maneuver: Its effect on intra-abdominal pressure and safety issues during resistance exercise. J. Strength Cond. Res. 27 2338\u20132345 (2013) 10.1519\/JSC.0b013e31827de07d.","DOI":"10.1519\/JSC.0b013e31827de07d"},{"key":"e_1_3_4_18_2","doi-asserted-by":"crossref","unstructured":"M. A. Caria F. Tangianu A. Concu A. Crisafulli O. Mameli Quantification of Spinning bike performance during a standard 50-minute class. J. Sports Sci. 25 421\u2013429 (2007) 10.1080\/02640410600718533.","DOI":"10.1080\/02640410600718533"},{"key":"e_1_3_4_19_2","doi-asserted-by":"crossref","unstructured":"G. R. Johnson L. Morawska The mechanism of breath aerosol formation. J. Aerosol. Med. Pulm. Drug Deliv. 22 229\u2013237 (2009) 10.1089\/jamp.2008.0720.","DOI":"10.1089\/jamp.2008.0720"},{"key":"e_1_3_4_20_2","doi-asserted-by":"crossref","unstructured":"L. Morawska Size distribution and sites of origin of droplets expelled from the human respiratory tract during expiratory activities. J. Aerosol Sci. 40 256\u2013269 (2009) 10.1016\/j.jaerosci.2008.11.002.","DOI":"10.1016\/j.jaerosci.2008.11.002"},{"key":"e_1_3_4_21_2","doi-asserted-by":"crossref","unstructured":"N. M. Wilson The effect of respiratory activity non-invasive respiratory support and facemasks on aerosol generation and its relevance to COVID-19. Anaesthesia 76 1465\u20131474 (2021) 10.1111\/anae.15475.","DOI":"10.1111\/anae.15475"},{"key":"e_1_3_4_22_2","doi-asserted-by":"crossref","unstructured":"C. E. George COVID-19 symptoms are reduced by targeted hydration of the nose larynx and trachea. Sci. Rep. 12 4599 (2022) 10.1038\/s41598-022-08609-y.","DOI":"10.1038\/s41598-022-08609-y"},{"key":"e_1_3_4_23_2","doi-asserted-by":"crossref","unstructured":"D. A. Edwards Exhaled aerosol increases with COVID-19 infection age and obesity. Proc. Natl. Acad. Sci. U.S.A. 118 e2021830118 (2021) 10.1073\/pnas.2021830118. e2021830118","DOI":"10.1073\/pnas.2109720118"},{"key":"e_1_3_4_24_2","doi-asserted-by":"crossref","unstructured":"J. D. MacDougall Factors affecting blood pressure during heavy weight lifting and static contractions. J. Appl. Physiol. 1985 1590\u20131597 (1992) 10.1152\/jappl.1992.73.4.1590.","DOI":"10.1152\/jappl.1992.73.4.1590"},{"key":"e_1_3_4_25_2","unstructured":"Guidebook sports accomodations (in Dutch) Handboek Sportaccomodaties; J. P. E. Ariens T. A. Joosten W. Schriemer Ed. (ISA Sport NOC*NSF Arko Sports Media BV 2008)."},{"key":"e_1_3_4_26_2","volume-title":"Guidelines for Acces Indoor Sports Accomodations","author":"Stichting Onbeperk Sportief","year":"2014","unstructured":"Stichting Onbeperk Sportief, Guidelines for Acces Indoor Sports Accomodations (In Dutch, Richtlijnen Toegankelijkheid Indoor Sportaccomodaties, 2014)."},{"key":"e_1_3_4_27_2","doi-asserted-by":"crossref","unstructured":"A. Garzona-Navas Mitigation of aerosols generated during exercise testing with a portable high-efficiency particulate air filter with fume hood. Chest 160 1388\u20131396 (2021) 10.1016\/j.chest.2021.04.023.","DOI":"10.1016\/j.chest.2021.04.023"},{"key":"e_1_3_4_28_2","volume-title":"StatPearls","author":"Weir C. B.","year":"2019","unstructured":"C. B. Weir, Arif Jan, BMI classification percentile and cut off points in StatPearls (StatPearls Publishing, 2019)."},{"key":"e_1_3_4_29_2","doi-asserted-by":"crossref","unstructured":"G. Buonanno L. Morawska L. Stabile Quantitative assessment of the risk of airborne transmission of SARS-CoV-2 infection: Prospective and retrospective applications. Environ. Int. 145 106112 (2020) 10.1016\/j.envint.2020.106112.","DOI":"10.1016\/j.envint.2020.106112"},{"key":"e_1_3_4_30_2","doi-asserted-by":"crossref","unstructured":"G. Buonanno L. Stabile L. Morawska Estimation of airborne viral emission: Quanta emission rate of SARS-CoV-2 for infection risk assessment. Environ. Int. 141 105794 (2020) 10.1016\/j.envint.2020.105794.","DOI":"10.1016\/j.envint.2020.105794"},{"key":"e_1_3_4_31_2","doi-asserted-by":"crossref","unstructured":"G. Buonanno Link between SARS-CoV-2 emissions and airborne concentrations: Closing the gap in understanding. J. Hazard. Mater. 428 128279 (2022) 10.1016\/j.jhazmat.2022.128279.","DOI":"10.1016\/j.jhazmat.2022.128279"},{"key":"e_1_3_4_32_2","doi-asserted-by":"crossref","unstructured":"F. Arpino Risk of SARS-CoV-2 in a car cabin assessed through 3D CFD simulations. Indoor Air 32 e13012 (2022) 10.1111\/ina.13012. e13012","DOI":"10.1111\/ina.13012"},{"key":"e_1_3_4_33_2","doi-asserted-by":"crossref","unstructured":"L. Stabile A. Pacitto A. Mikszewski L. Morawska G. Buonanno Ventilation procedures to minimize the airborne transmission of viruses in classrooms. Build. Environ. 202 108042 (2021) 10.1016\/j.buildenv.2021.108042.","DOI":"10.1016\/j.buildenv.2021.108042"},{"key":"e_1_3_4_34_2","doi-asserted-by":"crossref","unstructured":"A. Mikszewski L. Stabile G. Buonanno L. Morawska The airborne contagiousness of respiratory viruses: A comparative analysis and implications for mitigation. Geosci. Front. 20 101285 (2021) 10.1016\/j.gsf.2021.101285.","DOI":"10.1101\/2021.01.26.21250580"},{"key":"e_1_3_4_35_2","doi-asserted-by":"crossref","unstructured":"A. Mikszewski L. Stabile G. Buonanno L. Morawska Increased close proximity airborne transmission of the SARS-CoV-2 Delta variant. Sci. Total Environ. 816 151499 (2022) 10.1016\/j.scitotenv.2021.151499.","DOI":"10.1016\/j.scitotenv.2021.151499"},{"key":"e_1_3_4_36_2","doi-asserted-by":"crossref","unstructured":"P. Gale Thermodynamic equilibrium dose-response models for MERS-CoV infection reveal a potential protective role of human lung mucus but not for SARS-CoV-2. Microb. Risk Anal. 16 100140 (2020) 10.1016\/j.mran.2020.100140.","DOI":"10.1016\/j.mran.2020.100140"},{"key":"e_1_3_4_37_2","doi-asserted-by":"crossref","unstructured":"A. Henriques Modelling airborne transmission of SARS-CoV-2 using CARA: Risk assessment for enclosed spaces. Interface Focus 12 20210076 (2022) 10.1098\/rsfs.2021.0076.","DOI":"10.1098\/rsfs.2021.0076"},{"key":"e_1_3_4_38_2","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-022-18279-5"},{"key":"e_1_3_4_39_2","doi-asserted-by":"crossref","unstructured":"V. Stadnytskyi C. E. Bax A. Bax P. Anfinrud The airborne lifetime of small speech droplets and their potential importance in SARS-CoV-2 transmission. Proc. Natl. Acad. Sci. U. S. A. 117 11875\u201311877 (2020) 10.1073\/pnas.2006874117.","DOI":"10.1073\/pnas.2006874117"},{"key":"e_1_3_4_40_2","unstructured":"W. C. Adams Measurement of breathing rate and volume in routinely performed daily activities: Final report; Davis (1993)."},{"key":"e_1_3_4_41_2","doi-asserted-by":"crossref","unstructured":"International Commission on Radiological Protection Human respiratory tract model for radiological protection. A report of a Task Group of the International Commission on Radiological Protection. Ann ICRP 24 1\u2013482 (1994) 10.1016\/0146-6453(94)90029-9.","DOI":"10.1016\/0146-6453(94)90018-3"},{"key":"e_1_3_4_42_2","doi-asserted-by":"crossref","unstructured":"S. N. Rudnick D. K. Milton Risk of indoor airborne infection transmission estimated from carbon dioxide concentration. Indoor Air 13 237\u2013245 (2003) 10.1034\/j.1600-0668.2003.00189.x.","DOI":"10.1034\/j.1600-0668.2003.00189.x"},{"key":"e_1_3_4_43_2","doi-asserted-by":"crossref","unstructured":"B. G. Wagner B. J. Coburn S. Blower Calculating the potential for within-flight transmission of influenza A (H1N1). BMC Med. 7 81 (2009) 10.1186\/1741-7015-7-81.","DOI":"10.1186\/1741-7015-7-81"},{"key":"e_1_3_4_44_2","doi-asserted-by":"crossref","unstructured":"G. N. Sze To C. Y. H. Chao Review and comparison between the Wells-Riley and dose-response approaches to risk assessment of infectious respiratory diseases. Indoor Air 20 2\u201316 (2010) 10.1111\/j.1600-0668.2009.00621.x.","DOI":"10.1111\/j.1600-0668.2009.00621.x"},{"key":"e_1_3_4_45_2","doi-asserted-by":"crossref","unstructured":"T. Watanabe T. A. Bartrand M. H. Weir T. Omura C. N. Haas Development of a dose-response model for SARS coronavirus. Risk Anal. 30 1129\u20131138 (2010) 10.1111\/j.1539-6924.2010.01427.x.","DOI":"10.1111\/j.1539-6924.2010.01427.x"},{"key":"e_1_3_4_46_2","doi-asserted-by":"crossref","unstructured":"L. Stabile G. Buonanno A. Frattolillo M. Dell\u2019Isola The effect of the ventilation retrofit in a school on CO2 airborne particles and energy consumptions. Build. Environ. 156 1\u201311 (2019) 10.1016\/j.buildenv.2019.04.001.","DOI":"10.1016\/j.buildenv.2019.04.001"}],"container-title":["Proceedings of the National Academy of Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pnas.org\/doi\/pdf\/10.1073\/pnas.2220882120","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,9,21]],"date-time":"2023-09-21T08:58:45Z","timestamp":1695286725000},"score":1,"resource":{"primary":{"URL":"https:\/\/pnas.org\/doi\/10.1073\/pnas.2220882120"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,2,21]]},"references-count":46,"journal-issue":{"issue":"9","published-print":{"date-parts":[[2023,2,28]]}},"alternative-id":["10.1073\/pnas.2220882120"],"URL":"https:\/\/doi.org\/10.1073\/pnas.2220882120","relation":{},"ISSN":["0027-8424","1091-6490"],"issn-type":[{"value":"0027-8424","type":"print"},{"value":"1091-6490","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,2,21]]},"assertion":[{"value":"2022-12-16","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2023-01-06","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2023-02-21","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e2220882120"}}