Normal breathing
To understand breathing we should be aware of the normal breathing pattern. In normal breathing at rest, there are small in breaths (inhalation) followed by the out breaths (exhalation). The out breath is followed by an automatic pause (or period of no breathing) for about 1 to 2 seconds.
Most of the work of inhalation when we are at rest is done by the diaphragm, the main breathing muscle. The intercostal muscles, which are situated between each of the ribs and some of the muscles in chest and neck are known as the accessory muscles of breathing. They can become active to increase air flow in and out of the lungs during exercise or activity. Think about how an athlete is breathing at the end of a race. They are breathing faster and using accessory muscles to get more air in to their lungs. As they recover the breathing rate returns to normal.
Exhalation is passive (no active muscle activity) and is caused by the natural elastic recoil of the lung tissue and is accompanied by the relaxation of all breathing muscles.
When we are at rest this is how normal breathing, usually appears:
- Breathing in (inhalation) for 1 to 1.5 seconds.
- Breathing out (exhalation) for 1.5 to 2 seconds.
- An automatic pause of almost no breathing for 1 to 2 seconds.
Each breath contains around 500-600 ml of air, this is called the Tidal Volume (the depth of inhalation).
People usually take around 10-15 breaths per minute when resting. This is described as the Respiratory Rate.
Normal breathing is:
- Slow and regular, breathing in and out through the nose only.
- Invisible - No effort should be visible- the diaphragm should be moving gently.
- Quiet with:
- No panting.
- No wheezing.
- No sighing.
- No deep inhalations or exhalations.
You have reached the end of Topic 1 - Anatomy and Physiology.
It is strongly recommended that you work through each topic before attempting the topic assessment.
