Mechanics of Breathing Function of the Muscular System

2 Feb

yoga breathing 2

Respiratory muscles are divided into two groups: primary muscles (essential for full breathing) and secondary muscles, which are auxiliary helpers, and help to adapt and control breath. The roles of these muscle groups should never be reversed, because secondary muscles do not have the same stamina to be the prime movers for breathing, and are very inefficient and energy consuming.

The principle muscles of respiration include:

  1. Diaphragm. Responsible for 75% of the respiratory effort of relaxed breathing. It is a dome shaped like an umbrella or parachute.
  2. External intercostals. Responsible for 25% of the respiratory effort of relaxed breathing. They lift and expand the rib cage, increasing the negative density of air in the thoracic cavity, allowing air to be drawn into the lungs.

The Accessory Muscles of Respiration Include:

  • Intercostals. These assist the sliding action of the ribs during respiration, and are responsible for about 25% of the effort of relaxed breathing. During inhalation the external intercostals contract and the internal intercostals relax. During exhalation, the opposite occurs.
  • Abdominal muscles are involved in forced exhale, or a complete exhalation. Transversus abdominis have the most direct effect on breathing, because they originate in the same place as the diaphragm – the coastal cartilage at the base of the rib cage‟s inner surface. Rectus abdominus is a depressor of the ribs and sternum, and compresses the abdomen. Internal and external obliques compress the abdomen.
  • Scalenes help lift the upper ribs in full inhalation
  • Sternecleidomastoid is a flexor of the cervical spine, and elevator of the sternum and collarbones.
  • Upper trapezius goes from the base of the skull to the top of the shoulder blades, and assists in full inhalation.
  • Pectoralis major and minor protract the scapulae and depress the shoulder girdle, and assist in full inhalation.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s

%d bloggers like this: