How to Breath

Breathing is what keeps us all alive and is something we do every day unconsciously but probably pay little attention to. Correct breathing can help with muscle relaxation, reducing the onset of fatigue and helps create midline stability. When exercising, breathing properly is probably the most important thing to address.

Breathing simply involves inhaling oxygen and exhaling carbon dioxide. We need oxygen to help burn fuel to generate energy for our muscles and carbon dioxide is exhaled as a by-product, which acts as an indicator for us to change our breathing. Just like a fire, oxygen is needed for a fire to burn and carbon dioxide is the smoke or by-product created from generating the energy. So to improve breathing efficiency and performance, more oxygen needs to be inhaled and more carbon dioxide needs to be exhaled from the body. The question is how can we improve this? It is important to first better understand the mechanics of breathing.

Breathing mechanics

Inhalation and expiration can be explained by the principle of Boyle’s law, which states that air will move from an area of high pressure to an area of low pressure.


During inhalation the pressure within the lungs becomes less than the pressure outside of the lungs, which allows air to be drawn in. To generate this area of low pressure, the lungs need to expand and increase in volume. This is achieved by contracting the diaphragm and the external intercostal muscles (inspiratory muscles), which causes the diaphragm to flatten and the ribcage to be push upwards and outwards creating greater space for the lungs to expand. When these muscles fatigue other accessory muscles are used which won’t have the same effect of total volume inside the lungs.   


During exhalation the pressure inside the lungs increases causing air to leave the lungs. The pressure inside the lungs is increased by the inspiratory muscles relaxing, causing the diaphragm to rise and the ribcage to lower reducing the space within the lungs. During active exhalation, internal intercostal muscle are used to assist the lowering of the rib cage and the abdominal muscles are used to push the diaphragm upwards adding force to the exhalation.

Breathing when Exercising

When exercising, breaths will become shorter and faster, reducing the volume and pressure within the lungs thereby reducing the amount of air coming in. One of the reasons why marathon runners can run at such a high intensity for long periods of time is because they are incredibly efficient at utilising oxygen and removing carbon dioxide. However this is not just important for marathon runners but for any exercises or activities as good breathing efficiency and mechanics can reduce the effects of fatigue. During high intensity workouts the body will restrict blood flow and oxygen to the muscles at the extremities (arms/legs). This reflex is called the metaboreflex and is designed to maintain blood flow and oxygen to the inspiratory muscles. It is also why fatigue at the arms and legs will start to set in, as the delivery of oxygen to the muscles will become limited. At this point the muscles will be unable to meet the aerobic demands of energy required, which will reduce the rate the muscles can contract thereby forcing the intensity to drop. Whatever the exercise or activity it is very important to have good breathing efficiency and mechanics to maintain delivery of oxygen to the muscles to avoid the effect of muscles fatiguing. 

Diaphragmatic breathing

So to improve breathing efficiency and mechanics, pressure in the lungs needs to be lower when inhaling and higher when exhaling. In order to achieve this we need to breathe through our diaphragm or belly.

Diaphragmatic breathing involves inhaling through the nose and mouth focusing on contacting the diaphragm and expanding the space of the belly to reduce the pressure in the lungs instead of using the intercostal muscles to move the chest. During the exhalation phase it is focusing of using the abdominal muscles to expel the air. 

The best way to see if you are breathing through the diaphragm is to lie onto the floor with one hand on your belly and the other on your chest. If you are breathing through your diaphragm you will see the hand on your belly raise. However if the hand on the chest is raising then you are probably breathing more through the chest. Breathing through the chest over time can weaken the diaphragm. Practising diaphragm breathing or using the high altitude mask can help develop the strength of the diaphragm and respiratory muscles to help improve breathing efficiency and mechanics.

Brace position

Diaphragmatic breathing can be used to generate midline stability by adopting the braced position. The braced position is engaging the entire core, which is achieved by contracting the glutes, abdominals and breathing in using diaphragmatic breathing. The stability is created from filling the trunk with air creating pressure. Bracing is used in weightlifting to maintain the stability and tension of the midline when lifting heavy weights. It is also used when running and many other different exercises to maintain an upright position and create a good posture.     


Diaphragmatic breathing is commonly used in yoga and meditating, as it helps stimulate the parasympathetic nervous system, which allows our body to relax. Stress can cause short and shallow breaths, which happens as a result of the fight or flight reflex. So deep, diaphragmatic breathing and fully filling up the lungs with oxygen can help reduce stress and improve relaxation. It is also a common practise for patients suffering from cardiopulmonary disease to improve pulmonary function.

Wim Hof uses breathing techniques to going into a state of medication in order to withstand extremely cold environments. Some of his achievements have been incredible from running a marathon bare foot in the snow to swimming 50m under the ice. He talks about regaining a bit of your control autonomic nervous system through breathing thereby being able to control the temperature of your body.    


As discussed there are massive advantages of having good breathing mechanics and breathing through the diaphragm. Although diaphragmatic breathing may feel unnatural initially, if you look at a new born baby breath, you will see the belly moving indicating breathing through the diaphragm. Breathing maybe automatic, but it is important at times, to start thinking about breathing to try and regain a bit of control of your autonomic nervous system.  


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(3)   Lee M. Romer and Michael I. Polkey (2008). “Exercise-induced respiratory muscle fatigue: implications for performance”, Journal of Applied Physiology vol. 104no. 3879-888

(4)   Hof, Rosales (2012). “Becoming the Iceman”

(5)   DR Seals (2001). “Robin Hood for the lungs? A respiratory metaboreflex that ‘steals’ blood flow from locomotor muscles” – The Journal of physiology, Wiley Online Librar