Nose Breathing vs Mouth Breathing: Which Is Better and Why?

The short answer is: breathe through your nose, at rest, during sleep, and during most training.

Nose breathing filters, warms and humidifies the air, encourages the diaphragm to engage, carries nitric oxide into the lungs, and helps protect your airways. Mouth breathing bypasses these functions.

This article explains why, answers the exhale question, and shows you how to make the switch.

Whether you are a weekend warrior or a pro athlete, you understand how important it is to strengthen and condition your muscles for greater speed, power, and accuracy. But even if you are competing at a high level, it is likely you were never taught to make the connection between nose breathing and success.

Nose breathing has been the foundation of the Oxygen Advantage technique since the outset. Top athletes had been quietly using nose breathing exercises to excel, long before this knowledge became mainstream.

Why Nose Breathing Is Better Than Mouth Breathing

When it comes to sports performance, nose breathing is one of the simplest changes you can make. If you are still breathing through your mouth at rest and during easy training, it is a practice worth changing.

Research from the University of Milan, published in November 2021, found that young basketball players who followed a nasal breathing protocol during regular training showed improvements in physical fitness and pulmonary function [1].

When you breathe through your nose, many people find:

• Breathing is calmer and more economical at easy and moderate intensities
• Recovery feels easier
• The diaphragm engages better, supporting the core, spine and pelvic floor
• The nervous system is calmer, which can help with performance anxiety

How to Breathe Through Your Nose: When and Why

Goal-oriented people find it difficult to practice the maxim "less is more." The same competitive nature that helps you win can contribute to over-training, chronic fatigue, and a demoralising speed plateau.

We are conditioned to breathe hard and fast during training to "get more oxygen." We follow expert advice, only to find we are gassing out or struggling with exercise-induced asthma.

Contrary to common belief, less is often more when it comes to breathing too. Nose breathing slows your breathing and reduces unnecessary breathing volume at rest and easy intensities. This supports efficiency and a calmer nervous system.

Nose breathing is a 24/7 commitment. How you breathe during rest and sleep is just as important as how you breathe during competition. If you want to optimise your training, you must examine your breathing outside of physical exercise too.

Nose Breathing vs Mouth Breathing: Key Facts

Some coaches recommend breathing in through the nose and out through the mouth. Many people feel that nose breathing does not allow enough air into the lungs. Many believe mouth breathing provides more oxygen.

At rest and during easy exercise, it does not work that way. At maximal effort, the nose can limit airflow, so mouth breathing is normal during the hardest efforts.

By integrating nose breathing into your physical training, you can become more comfortable with air hunger and breathe more economically at easy and moderate paces.

Slower, deeper breaths mean a larger share of each breath reaches the lungs' air sacs. And the nose helps protect you from dehydration, airway irritation and infection.

Should You Exhale Through Your Nose or Mouth?

You should exhale through your nose.

In one study where people breathed cold, dry air, breathing in through the nose and out through the mouth increased nasal resistance by up to 200%, with congestion lasting up to ten minutes. Breathing in and out through the nose did not cause this [4]. Exhaling through the mouth also makes it easier to breathe out more air than you need.

Breathing in and out through the nose helps keep the airways clear and your breathing slower and calmer. The resistance of the nose also slows the exhale, which helps maintain lung volume.

The idea that exhaling through the mouth reduces air hunger is true in the short term. But if you breathe in and out through your nose during easy exercise, many people find they become more comfortable with air hunger over time, and breathing feels easier.

12 Benefits of Nose Breathing Over Mouth Breathing

1. The inside of your nose is lined with hairs and a mucous membrane covered in tiny hair-like cilia. Together they filter, warm and humidify inhaled air, trapping dust, allergens and other particles before they reach your lungs.
2. Some people argue you need to mouth breathe to bring in enough air during exercise. At easy and moderate intensities, the nose provides plenty of air, and the extra resistance slows the breath and adds a load to the breathing muscles [2].
3. In one study, runners adapted to nasal breathing breathed about 22% less air through the nose than the mouth while reaching a similar peak effort [3]. Breathing felt calmer and the breathing muscles do not have to work as hard at easy paces.
4. Nose breathing helps keep your airways clear. Breathing cold, dry air in through the nose and out through the mouth caused nasal congestion in one study [4]. If you have a stuffy nose, try the Oxygen Advantage nose-unblocking exercise and build up full nose breathing gradually.
5. Nose breathing is slower, and the resistance of the nose slows the exhale. This helps maintain lung volume, and slower breathing means less of each breath is wasted in the airways.
6. The air hunger during nose breathing encourages you to slow down until your breath is properly trained. This can help you keep easy sessions easy and avoid overtraining.
7. Nose breathing harnesses nitric oxide (NO) [5]. Nitric oxide is produced in the sinuses around the nose. It has antimicrobial properties against viruses, bacteria and other pathogens, and it helps open the blood vessels in the lungs.
8. When breathing matches the body's needs, the balance of oxygen and carbon dioxide (CO2) in the blood is maintained. CO2 and acidity help red blood cells release oxygen to the body. Habitually over-breathing, which often happens through an open mouth, lowers CO2 and makes this release less efficient.
9. Nose breathing during sleep is associated with less severe sleep apnea. Scientists found that during mouth breathing, apneas and oxygen desaturation tended to be worse [16].
10. Mouth breathing makes it easier to slip into upper-chest breathing. Nose breathing encourages the diaphragm to engage, which is an integral muscle of the core and supports spine stability.
11. During exercise, nose breathing may help mental focus, and it has been proposed to support coronary artery blood flow [6].
12. Nose breathing can reduce symptoms of exercise-induced asthma because it warms and humidifies the air before it reaches the airways.

How Nose Breathing Protects Against Pathogens and Infection

Few of the body's organs play as important a role as the nose. Its hairs, mucus and cilia, and the presence of nitric oxide, are some of the ways the nose helps defend against pathogens.

If you have a respiratory issue like asthma or allergies, mouth breathing can make symptoms worse. The nose is a vital part of the body's defence system. It filters out foreign materials that may contain bacteria or viruses while allowing oxygen into the lungs.

Effects of Pathogens on Respiration

Pathogens can affect respiratory function and cause a wide range of diseases, including:

• Respiratory infections: Viruses cause the most common types of respiratory infection, but bacteria and fungi can also cause similar illnesses. In people with asthma or COPD, symptoms may also be triggered by allergens or irritants in the air.
• Asthma: This chronic inflammatory disease causes narrowing of the airways and extra mucus, making it harder to move air in and out of the lungs. This leads to shortness of breath, coughing spasms and asthma attacks.

Keeping your mouth closed and breathing through your nose may reduce the chances that an inhaled pathogen affects your health.

What the Research Says: Nose vs Mouth Breathing

To gain a better understanding of nose breathing benefits, let us examine some clinical studies.

In this video, Oxygen Advantage founder Patrick McKeown chats to bestselling author James Nestor about the importance of nose breathing vs mouth breathing.

Mouth Breathing and Injury

Dysfunctional breathing has been linked to dysfunctional movement patterns [10]. Addressing mouth breathing and breathing pattern is a useful part of optimising your physical training.

Poor breathing mechanics have been associated with trigger points, repetitive strain, lower back and neck pain and even urinary leakage. In children, mouth breathing has been associated with postural changes [12].

A 2020 study reported that around a third of elite athletes experience urinary incontinence [7]. The diaphragm and pelvic floor work together, which is one reason good diaphragm function matters.

Asthma is also common in sports [8], and mouth breathing can make airway symptoms worse. Fit does not always mean healthy [9].

Over-Breathing Changes the Acidity of the Blood

Habitually breathing more than you need, which often happens with mouth breathing, depletes blood carbon dioxide. This can cause blood pH to increase, leading to respiratory alkalosis. Respiratory alkalosis means the blood is too alkaline. Breathing route alone does not determine whether someone is over-breathing, but mouth breathing makes it easier.

Its effects can include:

• Detrimental changes in the nervous system
• Alterations in physical and mental states
• Problems in the musculoskeletal system [10]
• Reduced release of oxygen to tissues and organs
• Increased pain perception
• Constriction of the blood vessels
• Development of myofascial trigger points

Each of these can change the normal motor control of skeletal muscles [11].

If you do get injured, good oxygen delivery supports recovery. Animal research suggests brief hypoxia may stimulate muscle stem cells, while prolonged hypoxia impairs muscle repair.

Can Nose Breathing Improve Sports Performance?

When you exercise, oxygen demand increases. To keep up with this demand, your breathing muscles work harder. When you breathe hard and fast through an open mouth at easy paces, breathing is less economical and the breathing muscles work harder than they need to.

During heavy, sustained efforts, tiring breathing muscles can trigger a reflex that reduces blood flow to the legs, adding to leg fatigue and making you slow down.

Remember, runners adapted to nasal breathing breathed about 22% less air through the nose. This greater economy can make easy and moderate running feel more controlled. In people who are not adapted, nasal-only breathing reduces peak performance at maximal effort, so it works best as a training tool at suitable intensities.

Nasal Obstruction Reduces Lung Volume and Oxygen Uptake

Swift AC, Campbell IT, McKown TM. Oronasal obstruction, lung volumes, and arterial oxygenation. Lancet. 1988.

Scientists examined lung volumes over 6 to 8 weeks during partial ongoing nasal obstruction and total overnight nasal blockage. Total lung capacity, functional residual capacity, and residual volume all decreased significantly with total nasal obstruction.

Researchers concluded that nasal resistance to expiration helps maintain lung volumes and may indirectly influence arterial oxygenation. In other words, when the nose is fully blocked and all breathing is through the mouth, lung volumes and oxygenation can be affected.

Furthermore, nasal strips for sports can help reduce mouth breathing during exercise. Read our full guide on nose strips for athletes and sports performance.

Nose Breathing Increases Arterial Oxygen Tension

Lundberg JO. Nitric oxide and the paranasal sinuses. Anat Rec (Hoboken). 2008.

Nitric oxide (NO) is released in the nasal airways in humans. During inspiration through the nose, NO follows the airstream to the lower airways and the lungs. Nasally derived NO has been shown to increase arterial oxygen tension and reduce pulmonary vascular resistance.

When you breathe through your nose, you inhale nitric oxide into your lungs, where it may help oxygen get into your blood.

The Nose Performs 30 Functions in the Body

Timmons BH, Ley R. Behavioral and Psychological Approaches to Breathing Disorders. 1994.

According to Dr. Maurice Cottle, who founded the American Rhinologic Society in 1954, the nose performs at least 30 functions, all of which are important supplements to the roles played by the lungs, heart, and other organs.

In the nose breathing vs mouth breathing debate, the nose has clear advantages at rest and during everyday activity. The mouth serves as a backup route if the nose is blocked or exercise is so intensive that a significantly greater volume of air is needed.

During Nose Breathing, Nitric Oxide Concentrations Increase

Lundberg J, Weitzberg E. Nasal nitric oxide in man. Thorax. 1999.

Nasal NO concentrations are higher at lower flow rates. When you breathe more slowly, you breathe a greater concentration of NO into your lungs.

Nose Breathing Supports Immune System Function

Lundberg J, Weitzberg E. Nasal nitric oxide in man. Thorax. 1999.

Among the various biological properties of nitric oxide in the nasal cavity are its effects on the growth of various pathogens including bacteria, fungi, and viruses. Nitric oxide offers a natural first line of immune defence against airborne pathogens.

Breathing Both In and Out Through the Nose Is Important

Strohl KP, Arnold JL, Decker MJ, Hoekje PL, McFadden ER. Nasal flow-resistive responses to challenge with cold dry air. J Appl Physiol. 1992.

When subjects breathed cold, dry air in through the nose and out through the mouth, nasal resistance increased by 200% within 1 minute and took 10 minutes to return to baseline. No such changes occurred when subjects breathed exclusively through the nose.

Breathing in through the nose and out through the mouth, especially in cold, dry conditions, can result in a stuffy nose that lasts up to ten minutes. If you breathe in and out through your nose during easy exercise, many people find breathing becomes easier over time.

Nose Breathing Improves Pulmonary Function

Airway physiology. Tidsskr Nor Laegeforen. 1999.

High nitric oxide levels in the nasal and paranasal airways contribute to the first line of defence against microorganisms. Autoinhalation of nasal NO may improve pulmonary function and other physiological processes.

The nitric oxide you inhale during nose breathing supports the function of your airways, lungs and blood vessels.

Nitric Oxide in the Nasal Airway and Ear, Nose and Throat Health

Am J Otolaryngol. 2001.

The surprisingly high concentrations of NO in the nasal airway and paranasal sinuses have important implications for the study of diseases in the ears, nose, and throat. This nitric oxide could potentially be useful in treating or preventing ENT conditions.

Maximal Oxygen Consumption: Nose Breathing vs Mouth Breathing

Morton, King, Papalia. Australian Journal of Science and Medicine in Sport. 1995.

During exercise, nasal breathing causes a reduction in the fraction of expired oxygen, indicating that a greater percentage of oxygen is extracted from each breath. This reflects slower, more economical breathing. It does not mean nasal breathing raises maximal oxygen uptake: in people who are not adapted, nasal-only breathing lowers peak oxygen uptake at maximal effort.

Nasal Nitric Oxide and Oxygen Uptake

Growth and Development. 2005.

Nitric oxide inhaled via nasal respiration has been reported to improve oxygen exchange efficiency in the lungs.

This is one more way nose breathing supports healthy lung function.

Mouth Breathing at Night: How It Affects Sleep and Performance

When sleep is poor, speed, endurance, strength, executive function, learning, attention, running performance, reaction time, mood, vigour, max bench press, leg press, deadlift, and recovery can all suffer [13/14].

In the run up to competition, it is normal to have trouble falling or staying asleep. Stress, a heavy training schedule, travel and jet lag can all lead to insomnia.

Daytime breathing habits may also affect sleep. In rodent studies, scientists identified an area of the brain that links breathing rhythm with arousal. Fast breathing during the day may contribute to hyperarousal of the sympathetic nervous system, which can make sleep harder [15].

Mouth breathing during sleep can affect airway health and sleep quality, and it is associated with more severe sleep apnea [16]. If you regularly breathe through your mouth at night, snore, or wake up unrefreshed, talk to your doctor about sleep-disordered breathing.

Sleep apnea is linked with poor cardiovascular health, depression, and sexual dysfunction. Even adolescent athletes can have sleep disorders, just as they can have asthma, colds and flu.

One study found sleep-disordered breathing is common in adolescent athletes and discussed its possible significance for heart health [17].

Sleep disorders are hard to self-diagnose. In a competitive atmosphere, it can feel like success equals "survival of the fittest." But mouth breathing during sleep is a serious matter that is unwise to ignore.

How to Switch to Nose Breathing: 8 Practical Steps

Discover ways to integrate Oxygen Advantage breathing exercises and tools into your daily routine.

1. Switch to nose breathing at rest and during easy exercise. This adds a load to breathing that strengthens the diaphragm. If you want to add more resistance, try nose breathing with a training mask.
2. During easy and moderate training, instead of pushing through with an open mouth, slow down and continue breathing through your nose. Read our full guide on how to breathe while running.
3. If you struggle to practice nose breathing due to a deviated septum or small nasal passages, use a nasal dilator. If your nose stays blocked, see a doctor, as there may be a structural cause.
4. Practice breathing exercises to engage your diaphragm, slow your breathing and reduce breathing volume, becoming more comfortable with air hunger. Track your progress with the BOLT score test.
5. If they are suitable for you, practice breath holding exercises to give your diaphragm a workout and create an altitude-like training stimulus. Never practice them in water, and avoid strong breath holds if you are pregnant or have a heart condition, high or low blood pressure, epilepsy or another serious medical condition.
6. Breathing heavily at night is associated with snoring. Spend 15 minutes before bed practicing a reduced breathing exercise. This can help calm your nervous system and settle your breathing.
7. Tape your mouth during sleep to support nose breathing at night. Used alongside breathing exercises, MyoTape can help build the habit, and many people report better sleep and recovery. Only tape if you can breathe comfortably through your nose. Mouth taping is not a treatment for sleep apnea.
8. You can use MyoTape during training too. Because it does not cover the lips, you can still communicate and hydrate while maintaining nose breathing support.

---

If you are interested in trying the OA method for yourself, why not try our online course, become a certified breathwork instructor, or find an Oxygen Advantage® instructor near you.

References

1. Cavaggioni L, et al. Effects of a nasal breathing protocol on physical fitness and pulmonary function in young basketball players. The Journal of sports medicine and physical fitness. 2021.
2. Cottle MH. The work, ways, positions and patterns of nasal breathing. American Rhinologic Society. 1987.
3. Dallam GM, McClaran SR, Cox DG, Foust CP. Effect of Nasal Versus Oral Breathing on VO2max and Physiological Economy in Recreational Runners. International Journal of Kinesiology and Sports Science. 2018;6(2):22-29.
4. Strohl KP, Arnold JL, Decker MJ, Hoekje PL, McFadden ER. Nasal flow-resistive responses to challenge with cold dry air. Journal of Applied Physiology. 1992;72(4):1243-1246.
5. Lundberg JO, Weitzberg E. Nasal nitric oxide in man. Thorax. 1999;54:947-952.
6. Dallam G, Foust C. Can Yoga Breathing / Pranayama Concepts Be Reasonably Extended to Conventional Endurance Training? W J Yoga Phys Ther and Rehabil. 2020.
7. Rodriguez-Lopez ES, et al. Prevalence of urinary incontinence among elite athletes of both sexes. Journal of Science and Medicine in Sport. 2020.
8. Carlsen KH. Mechanisms of asthma development in elite athletes. Breathe. 2012;8(4):278-284.
9. Maffetone PB, Laursen PB. Athletes: fit but unhealthy? Sports medicine-open. 2016;2(1):1-4.
10. Bradley H, Esformes J. Breathing pattern disorders and functional movement. International journal of sports physical therapy. 2014;9(1):28.
11. McLaughlin L, Goldsmith CH, Coleman K. Breathing evaluation and retraining as an adjunct to manual therapy. Manual therapy. 2011;16(1):51-52.
12. Neiva PD, et al. Postural disorders in mouth breathing children: a systematic review. Brazilian journal of physical therapy. 2018;22(1):7-19.
13. Marshall GJG, Turner AN. The importance of sleep for athletic performance. Strength and Conditioning Journal. 2016;38(1):61-67.
14. Fullagar HH. Sleep-related issues facing professional football players. PhD dissertation. 2017.
15. Yackle K, et al. Breathing control center neurons that promote arousal in mice. Science. 2017;355(6332):1411-1415.
16. Hsu YB, et al. Association Between Breathing Route, Oxygen Desaturation, and Upper Airway Morphology. The Laryngoscope. 2020.
17. Iso Y, et al. Prevalence and significance of sleep disordered breathing in adolescent athletes. ERJ open research. 2019;5(1).

FAQs

Q: What is the difference between nose breathing and mouth breathing?
A: The nose filters, warms, and humidifies incoming air, carries nitric oxide into the lungs, and adds resistance that slows the breath and encourages the diaphragm to engage. Mouth breathing bypasses these functions and makes upper chest breathing more likely.

Q: Is nasal breathing better than mouth breathing during exercise?
A: At easy and moderate intensities, yes. Nasal breathing protects the airways, slows the breath, and can make breathing more economical. At maximal effort the nose can limit airflow, so mouth breathing during the hardest efforts is normal.

Q: What are the health consequences of chronic mouth breathing?
A: Chronic mouth breathing has been associated with snoring, more severe sleep apnea, dry mouth, dental problems, poor sleep, and altered facial development in children, including narrow jaws and crooked teeth. If you mouth breathe at night or snore, it is worth discussing with your doctor or dentist.

Q: Can adults retrain themselves to breathe through the nose?
A: Yes. Adults can restore nasal breathing by practising nose-unblocking exercises, correcting daytime breathing volume with Breathe Light exercises, and using mouth tape at night to reinforce nasal breathing during sleep, provided they can breathe comfortably through the nose.

Q: Does nasal breathing produce nitric oxide?
A: Yes. Nitric oxide is produced in the paranasal sinuses and carried into the lungs during nasal breathing. It has antimicrobial properties and helps open the airways and blood vessels in the lungs.