The Role of the Nose for Physical Capacity

Nasal breathing as a prerequisite for global airway health and physical capacity,

1. Introduction The airways are traditionally divided into two segments, the upper and lower. The former consists of the nose, the paranaseal sinuses, the epipharynx, the oropharynynx, and the hypopharynx down to the level of the vocal cords. The latter involves everything below the vocal cords, including the trachea, the bronchi, the bronchioles, and the alveoli. The latter is the segment where the oxygen/CO2 exchange take place, critical for life. In this way, the upper and lower airways can be considered as two of a kind ((Steinsvag 2009). The role of the nose in this is to filter, temper and humidify the inspired air before entering the lungs. Further, the nose adds nitrogen monoxide, thereby optimizing the muco-ciliary activity and the ventilation-perfusion ratio in the lungs.

We know that there is a link between disorders in the upper and lower airways, both epidemiologically, patho-physiologically, and therapeutically (Fireman 2000, Thorstensen, Bugten et al. 2012, Bousquet, Schünemann et al. 2019, Oie, Dahlslett et al. 2020). What we know less about is the role for the nose and nasal breathing for physical capacity. That goes both for the ability of the average, healthy persons well as for patients with ie. asthma and COPD to perform daily life activities as well as exercise and for top athletes to perform their maximum oxygen demanding activities. Without this knowledge, we cannot make evidence based decisions about to what extent measures to open the nose medically and/or surgically should be considered to improve physical capacity at any level. The aim of the present project is to expand our knowledge in the field for the best of the ordinary man, patients with airway disorders, and athletes. 2. Needs description The main impact of the present project is an improved understanding of the role of the upper airways for physical capacity. Physical capacity is essential for the ability to be physically active, move around, exercise and perform sports at any level. Thus, it is essential for the general well-being for everybody, essential as a disease-preventing factor, and essential for athletes. We know that nasal obstruction has negative impact on the lower airways, sleep(Migueis, Thuler et al. 2016), taste and smell(Dileo and Amedee 1994) as well as general quality of life(Osborn and Sacks 2013). But we do not know much about how nasal obstruction affects physical capacity. It is possible to deduce that measures to reduce mucosal inflammation in the nose and to improve nasal patency may have beneficial effects. There is scientific support for this in that intranasal steroids, cromolyn, antihistamines, and decongestants(Bousquet, Schünemann et al. 2019), which provide relief of nasal symptoms in patients with both allergic rhinitis and asthma, will also improve the pulmonary symptoms in allergic asthma(Fireman 2000). Surgical management of sinonasal pathology can improve asthma(Dunlop, Scadding et al. 1999) In some studies, external nasal dilators have been shown to improve endurance (Ottaviano, Ermolao et al. 2017). However, this has been opposed by others(Adams and Peiffer 2017).

To be able to move around is important for most people. It is important for those with severe airway limitations/disabilities to be able to carry out elementary daily life activities as well as for most top athletes in their chase for trophies. Movement presupposes physical capacity at some level, from the lowest to the most extreme. When it comes to airway limitations, the focus usually is on the lower airways while the upper airways are forgotten. Given the unified airway concept, this is unfortunate,since optimizing the latter may have major impact on the global airway function. This implies reducing inflammation by medical means and/or improving patency by medical or surgical means, i.e. turbinate surgery, septal surgery and polypectomy.

Before involving measures on the upper airway to improve physical capacity, we need to know more about the potential. That is the motivation for this investigation. This research project may have an impact for patients, the ordinary man, and athletes where the airways may be a limiting factor for their daily life activities and self-expression.