A lot of equestrians hold their breath, be it due to psychological stress during competition, or increase intra-abdominal pressure during landing in the jumping sports. Aside from the adverse physiological effects of breath holding such as reduced oxygen, there are a whole lot of biomechanical effects that come with mal-adaptive breathing. I've dedicated this month to learning more about the importance of breathing and it's effects on the body, and I have to admit much of my new found knowledge comes from the incredible Dr Kathy Dooley!
My first take home is the importance of nose breathing! You probably know that horses are obligate nasal breathers, they cannot breathe with their mouth, and we should learn a valuable lesson from that.
Breathing from the mouth ensures "chest breathing" where we draw air into the chest area using the intercostals and other accessory breathing muscles rather than breathing deeply throughout the lungs via the diaphragm. This develops certain muscles such as the scalenes (in the neck) whose job involves elevating the first rib, flexing and laterally flexing the neck. Tightness in the scalenes can adversely affect the neck, but can also have more global effects for example on grip strength due to their close situation to some major nerves.
The Phrenic nerve is closely situated to the scalenes, and the job of this nerve is to innervate the... wait for it... diaphragm!!!! Therefore tightness of the scalenes may further limit belly breathing.
Overuse of the scalenes can also compress the long thoracic nerve, which innervates the anterior serratus muscle. The anterior serratus is the most important muscle in shoulder stability, therefore, your bad breathing, can affect shoulder stability too...
Research suggests that controlled and directed breathing can reduce recruitment of the sternocleidomastoid muscle, the muscle that gives our head and neck the forward position often seen in Equestrians. Diaphragmatic breathing also improves our ability to maintain intra-abdominal pressure, and increases core strength*.
Constant mouth breathing is a "Pandemic" and can have deleterious effects on health to include bad breath, sleep apnea and reduced Nitric Oxide in the blood. Nitric Oxide is produced in the paranasal sinuses and is excreted continuously into the nasal airways of humans. Nasal breathing improves levels of nitric oxide in the blood stream which aids digestion, reduces anxiety and depression and improves athletic performance.
So.. if you're interested in improving your nasal breathing, here is a link explaining why you should tape your mouth shut when sleeping!
... and next time you come for a treatment, don't be surprised if I do some breathing techniques with you.