key: cord-0817293-jshmac42 authors: Ufnalska, Sylwia title: Why Not Encourage Physical Activity Outdoors and Inhaling Through the Uncovered Nose During the Coronavirus Lockdown? date: 2020-12-03 journal: Mater Sociomed DOI: 10.5455/msm.2020.32.315-316 sha: 8d12ab52799c94f29a31116dd5e60444aeebb351 doc_id: 817293 cord_uid: jshmac42 nan Why Not Encourage Physical Activity Outdoors and Inhaling Through the Uncovered Nose During the Coronavirus Lockdown? To stop the spread of COVID-19, more and more countries worldwide introduce progressive restrictions and promote the "stay at home" policy, requiring that time spent outside home should be minimized. For families living together, however, this policy is against the official WHO recommendations to avoid the three Cs: spaces that are closed, crowded and/or involve close contact 1 . Consequently, lockdown greatly facilitates transmission of the disease among family members, so unintentionally it contributes to the spread of COVID-19. This undesirable side effect is aggravated in autumn and winter because of poor ventilation indoors, so the problem needs to be solved urgently. Moreover, staying at home for a long time increases the risk of depression and many other serious diseases. Fortunately, there exists a good solution: promotion of physical activity 2 , mostly outdoors 3 . Firstly, it limits the time spent indoors with people who may have been infected. Secondly, both physical and mental health benefits of regular exercise have been reported, not only for sports but also for less strenuous outdoor activities, like strolling 4 , gardening 5 and birdwatching 6 . All these activities can be easily practised also in cities, e.g. by planting wilted winter-hardy potted flowers in lawns or on roadsides 7 . Thirdly, our lungs can be ventilated more effectively thanks to body movements and fresh air. As emphasized by WHO infographics, 1 m is a safe distance outdoors 1, 8 , and masks should not be used while exercising, as they reduce the ability to breathe comfortably and promote the growth of microorganisms 9 . As evidenced by Prof. Lidia Morawska and her research team, aerosolization of secretions lubricating the vocal chords is a major source of droplets 10 (which play a major role in the spread of COVID-19 11 ), so covering the mouth is crucial during conversations, singing and coughing. In contrast, the benefits of uncovering the nose seem to outweigh its disadvantages. Our nasal cavities produce nitric oxide (NO), which intensifies blood flow through our lungs and boosts oxygen levels in the blood, as explained by Prof. Louis Ignarro (one of Nobel Prize winners in 1998). He emphasizes that "breathing in through the nose delivers NO directly into the lungs, where it helps fight coronavirus infection by blocking the replication of the coronavirus in the lungs" 12 . Admittedly, sneezing with an uncovered nose could pose a risk, but chiefly indoors, and the WHO recommends using one's elbow or tissue then. The exposed nose would allow us breathing comfortably and benefit from the favourable effects of NO produced in the nasal cavity. The use of face masks seems justified primarily in closed spaces (public buildings, public transport, etc.), crowded places, and during closerange conversations (also in private settings and outdoors). Thus it can be concluded that the effectiveness of the current coronavirus strategies in many countries could be increased if physical activity outdoors was encouraged and we covered only our mouth in public places outdoors. In my opinion, the new policy (promoted e.g. as #moveoutdoors), could help to reduce the rate of COVID-19 transmission and would be highly beneficial for both our physical and mental health (13) . World Health Organization. Coronavirus disease (COVID-19) advice for the public World Health Organization. #HealthyAtHome-Physical activity Physical activity outdoors as an alternative to lockdown: the Three Cs Strategy. Med Arch Kopf hoch -das kleine Überlebensbuch: Soforthilfe bei Stress, Ärger und anderen Durchhängern Gardening is beneficial for health: A meta-analysis Psychiatra patrzy na ptaki w czasie pandemii COVID-19: obserwacje, introspekcje, interpretacje Strolls and gardening: can they help to fight the pandemic? Science Writing, Editing and Publishing Conference Avoid the Three Cs Can people wear masks while exercising Size distribution and sites of origin of droplets expelled from the human respiratory tract during expiratory activities How can airborne transmission of COVID-19 indoors be minimised? Environment International 2020 The right way to breathe during the coronavirus pandemic. The Conversation Abstracts of the Days of AMNuBiH 2020 and SWEP 2020