橫隔膜功能之於核心穩定-下 DIAPHRAGM FUNCTION FOR CORE STABILITY

Posted by Hans Lindgren DC on 29 April 2017 | 0 Comments

Tags: Core, Translated

簡介

良好的核心穩定須仰賴橫膈膜執行呼吸以及姿勢維持的雙功能來維持。DNS的創始者Kolar等學者的研究顯示，橫膈膜是重要的姿勢穩定肌肉，而且是可以被自主控制，同時也可以自發性的執行呼吸與姿勢穩定的功能。

然而，近代的核心穩定運動理論中，橫膈膜幾乎根本沒有被提及。在許多專家提供的核心穩定概念中，都完全沒有提到橫膈膜。雖然橫膈膜在近年開始被提到了。可惜的是，仍只有運動處方的最後才強調，在運動過程中要保持橫膈呼吸。

In “core stability from the inside out”we established that proper core stabilization is generated through the diaphragm’s dual function of respiration and postural support. Kolar et al (7) (8) and many others (see references for “Core stability from the inside out”) have shown that the diaphragm is an important muscle for postural stabilization, and also that it is under voluntary control and can perform its respiratory function and postural tasks simultaneously.

It was not that long ago when the diaphragm almost never even got mentioned in the discussions of core and core-stability training. There are still many “experts” who give advice regarding core-stabilization but completely fail to mention the diaphragm. There has however, been more frequent mentioning of diaphragm breathing lately. Unfortunately it often only gets added to exercise prescriptions as final comment of “make sure to maintain diaphragm breathing while exercising”.

1. 何謂橫膈呼吸？

人是無法不依靠橫膈呼吸的。不論你想不想，所有的呼吸都是需要藉由橫膈膜完成，除非你有些隱疾，讓你無法使用橫膈。在一般的呼吸容積中，橫膈的作用約占了80%。

What is diaphragm breathing?

You cannot avoid using your diaphragm when breathing even if you try to! All breathing is performed by the diaphragm whether you want to or not unless there is a medical condition preventing you from using it. The diaphragm is responsible for about 80% of all the respiratory work in normal tidal breathing.

 2. 橫膈的解剖和肌動學

橫膈膜是一個圓頂形狀的肌肉；分隔胸腔與腹腔。中間拱形部分是無法收縮的肌腱，往下會輻射狀的連接到胸廓下段內側。橫膈膜的肋骨端連接到劍突及最後6根肋骨及肋軟骨內側。橫膈膜腳纖維從拱形韌帶延伸連接到上段腰椎。右邊的橫膈膜腳連接到腰椎一到三節，左邊連接到腰椎一二節。胸廓下緣與橫膈膜貼合的區域稱為Zone of apposition (ZOA)，這個區域對橫膈膜功能非常重要。這個區域受到腹肌控制且影響橫膈的張力。橫膈的位置及與下段胸廓的係大大的影響了橫膈膜的效能。

Diaphragm    

The diaphragm is a dome shaped muscle separating the thoracic and abdominal cavities. It has a non-contractile central tendon (arcuate) from which muscles radiate caudally and outwards to insert into the inner aspect of the lower ribcage. The costal diaphragm inserts into the xiphoid process and the inner surface of the 6 lower ribs and costal cartilages. The crural fibres span from the arcuate ligament and insert into the bodies and discs of the upper lumbar vertebrae. The right crural diaphragm inserts into L 1-3 vertebrae while the left only inserts into L 1-2. The area of attachment (apposition) between the diaphragm and the ribcage is referred to as the zone of apposition (ZOA) which is of great importance for proper diaphragm function.  The zone of apposition is controlled by the abdominal muscles and affects diaphragmatic tension. The diaphragm’s efficiency largely depends upon its position and anatomical relationship with the lower ribcage.

 3. 橫膈膜與肋骨貼合區域 (ZOA)

ZOA是個堅硬卻面積變化很大的區域。站姿休息時，這個區域占了內側胸廓30%。橫膈腳在吸氣的時候會從這個區域離開胸廓，使得橫膈收縮往下。ZOA在平靜吸氣時會減少15mm，同時橫膈頂端仍會繼續保持原本的大小及形狀。在肺部最大吸氣量時，這個區域會接近0mm。ZOA肌肉縮短是主要造成橫膈膜在胸廓垂直軸向位移的原因。如果ZOA受限，會造成橫膈在胸廓上的呼吸動作減少。

Zone of apposition (ZOA)

The zone of apposition makes up a substantial but varying area of the ribcage. In standing at rest the human ZOA represents about 30% of the total surface area of the inner ribcage (11). The crural part of the diaphragm peels away from the ribcage at the zone of apposition (10) (9) (12) during diaphragm contraction to allow the diaphragm to descend during inspiration. The zone of apposition decreases by about 15mm during quiet inspiration while the dome of the diaphragm almost remains constant in shape and size. At maximum inspiratory capacity of the lungs the ZOA is almost zero. The shortening of the apposed muscle fibres are mainly responsible for the diaphragm’s axial displacement during inspiration (2) (6). A smaller zone of apposition will result in reduced inspiratory action of the diaphragm on the ribcage (9).

 4. 橫膈膜功能

吸氣時，橫膈膜收縮往下，有如活塞進入腹腔內。造成胸腔負壓，讓空氣進入肺，也同時增加了腹內壓。

橫膈是主要的呼吸肌，許多人並沒有正確的活化它。失能的呼吸模式是造成下背痛的常見因素，此因素比其他危險因子要更能預言下背痛的發生。

Diaphragm function

During inspiration the diaphragm contracts and moves down caudally like a piston into the abdominal cavity, which creates a negative pressure in the thoracic cavity that forces air into the lungs and simultaneously increases the intra-abdominal pressure.

The diaphragm is our primary breathing muscle and yet many individuals have very little awareness of how to activate it properly. Dysfunctional breathing patterns are a common contributing factor for low-back pain conditions, and it is actually often a stronger predictor for low back pain than other established risk factors (15).

 5. 正確的橫膈膜呼吸與腹式呼吸（belly breathing)一樣嗎？

橫膈膜呼吸一直被視為腹式呼吸，其實未必。當橫膈膜收縮下降到腹腔，腹內壓增加會造成腹部膨脹。有效的橫隔呼吸中，腹壁肌肉的膨脹應該是3D的，所有的方向都輕微的擴張。腹壁所有肌肉會以離心收縮的方式來對抗橫膈所給予的壓力。腹壁肌肉對抗橫膈膜的能力同時也對橫膈膜長度與張力之間是非常重要的控制。

骨胳肌中，包括橫膈都有長度與張力之間的關係，即長度縮短後（收縮），收縮的力量也隨之下降。這股由腹壁肌肉離心收縮製造的力量可以維持橫膈膜與肋骨貼合的區域以及橫膈圓頂的形狀。進而促進了橫膈力量的增加。腹式呼吸只有擴張腹腔的前半部並沒有提供橫膈膜任何的阻力，事實上，還減少了橫膈有效收縮的能力。

Is proper diaphragm breathing the same as belly breathing?

Diaphragm breathing is often referred to as belly breathing, but that is not correct. When the diaphragm contracts and descends into the abdominal cavity the intra-abdominal pressure increases and will distend the abdominal wall.  In efficient diaphragm breathing the distension of the abdominal wall should be three dimensional with a slight expansion in all directions. The abdominal wall should oppose the action of the diaphragm with an eccentric contraction of all the abdominal muscles. The opposing action of the abdominal wall is very important in controlling the length tension relationship of the diaphragm muscle.

Any skeletal muscle, including the diaphragm, has a length-tension relationship where decreased length (contraction) decreases the force of the contraction. The opposing forces created by the abdominal muscles in their eccentric contraction maintain the zone of apposition and the dome shape of the diaphragm, and thereby facilitates the increased force of the diaphragm.  Belly breathing only distends the abdomen forward, which does not offer any resistance to the diaphragms motion and will therefore actually reduce the diaphragm’s ability to contract efficiently.

 6.理想的橫膈膜呼吸

理想的橫膈膜呼吸主要是下肋骨側方的擴張。橫膈膜收縮時，肋骨端橫膈（ZOA)的收縮會擴張下段胸廓以及腹壁，橫膈膜腳端，由於解剖走向連接到腰椎，收縮時，只會造成腹部往前的方向。ZOA可以將腹內壓傳送到胸廓。形成吸氣時，橫膈膜收縮影響胸廓使其往外的機制。這是橫膈膜在連接胸廓處對肋骨形成往外、往上的動作（外旋）。

Proper diaphragm breathing

Ideal diaphragm breathing expands the lower ribs outwards in a mainly lateral direction. The costal part of the diaphragm (ZOA) expands both the lower ribcage and the abdominal wall when contracting (the crural part only displaces the abdomen forward with its contraction directed forward due to its attachments on the lumbar spine). The apposition of the diaphragm to the inner ribcage wall allows for transmission of intra-abdominal pressure to the ribcage, which provides a mechanism whereby the diaphragmatic contraction drives the ribcage outwards during inspiration (16) (11).  Adding to this is the direct outward lifting motion (external rotation) the diaphragm exerts on the ribs at its insertions to the ribcage.

 7. 良好橫隔膜呼吸的特徵

下段胸廓應該要有擴張而且胸腔不會往頭側移動。伴隨著腹部肌肉協同做輕微擴張動作，並透過離心收縮來控制腹內壓。

Signs of proper diaphragm breathing

There should be an expansion of the lower ribcage without any cranial movement of the chest, accompanied by a synchronized activity of the entire abdominal wall which expands slightly while controlling the IAP by an eccentric contraction.

 8. 失能的呼吸模式

引起呼吸失能的身心原因往往是不可分開的．因此，呼吸失能也無法被簡單定義．無論是姿勢上、發育上、醫學上或情緒上的原因，呈現出來的失能特徵都非常的相似。失能的呼吸模式包括：上胸廓呼吸並伴隨下肋骨擴張不全或無法擴張。且有不同步或矛盾的呼吸模式 (協調出現障礙)。

矛盾的呼吸模式包括: 吸氣時，腹部往內收及下段胸廓窄收而非往外擴張。以MRI觀察矛盾呼吸模式在深層呼吸中的橫膈動作：吸氣時，肋骨端的橫膈會往上移動；腳端則會往下移動．吐氣時則呈現相反動作模式。

Dysfunctional breathing patterns

Physical and psychological causes of breathing dysfunction can be hard to separate, and dysfunctional breathing can therefore not be simply defined. Whether the cause is postural, developmental, medical or emotional, the presentation is always very similar. Breathing patterns regarded as dysfunctional include upper chest breathing with decreased or absent lateral expansion of the lower ribcage, with a tendency for asynchronous and paradoxical breathing.  

During paradoxical breathing the belly is drawn in and the lower ribcage narrows rather than expands during inspiration (13).  Paradoxical movement of the diaphragm has been evaluated using MRI during deep breathing which showed an upward movement of the costal part of the diaphragm when the crural part moved downward during inspiration, and the opposite relationship during expiration.

9. 姿勢相關的呼吸失能特徵

胸腔

肋骨通常在僵硬、抬高的位置，此位置造成肋骨的外翻。肋骨端的橫膈纖維也被往上拉離原本該有的正常圓頂形狀，進而走向變得更加垂直。在這個位置下，ZOA區域減少，橫膈收縮也被影響。同時，下段肋骨外翻的現象也是常見的問題。

呼吸輔助肌

吸氣時，斜角肌、胸鎖乳突肌、上斜方肌、胸肌等肌肉，因為肋骨過度的垂直活動及肩膀的聳起，常處在高張的狀態。胸腰椎的伸肌群也因為缺乏良好的的核心穩定，也會呈高張狀態來協助維持脊椎穩定。每個呼吸都呈現出肩膀聳起及背部伸直的錯誤動作模式，因此呼吸失能是造成背部、頸部僵硬與疼痛的常見原因。

腹壁肌肉

腹部肌肉不平衡活化伴隨腹內外斜肌、腹橫肌的肌張力減少，在呼吸失能族群中是很常見的。而腹直肌(尤其上段纖維)反呈現高張狀態。呼吸失能的典型特徵為:平躺姿勢下，腹直肌明顯往上抬升而下外側腹壁凹陷空洞。腹部的姿勢肌（tonic muscle)與相位肌（phasic muscle)協同收縮來協助橫膈的呼吸功能。

Postural signs of dysfunctional breathing

The chest

The ribcage is often stiff and held in an elevated position which externally rotates the ribs and pulls the costal diaphragm fibres from its normal dome shaped position to a more straight and vertical position. This position reduces the zone of apposition and thereby the diaphragm’s contraction. Spontaneous flaring of the lower ribs is often observed.

Accessory breathing muscles

Muscles including Scalenes, SCM, upper trapezius and Pectoralis are often hypertonic and over-developed from the increased vertical movement of the ribcage and elevation of the shoulders during inspiration. The thoracolumbar extensor muscles are hyper-tonic attempting to stabilize the spine in the absence of proper core stabilization.  Every breath involves a shoulder elevation and a back extension. Breathing dysfunction is a common cause for stiffness and pain in the back and neck.

Abdominal wall

An imbalanced activation of the abdominal wall with reduced muscle tone in the external and internal oblique muscles as well as the transversus abdominis is common. There is usually hyper-tonicity of the rectus abdominis especially in the upper sections. A typical sign of dysfunctional breathing is therefore a marked elevation of the rectus abdominis and concave hollows at the lower lateral abdominal wall in supine. Both phasic and tonic synchronized contractions of the abdominal wall assist the function of the diaphragm during respiration.

無力的腹肌

腹肌無力會弱化橫膈的功能。如果腹肌沒有在橫膈收縮時提供適當的阻力，腹肌會往下移動卻無法明顯增加腹內壓。腹肌對抗橫膈膜收縮的機制，幫助維持ZOA與橫膈圓頂形狀的正常位置。

高張的腹肌

如果腹肌收得太緊，會造成中央肌腱無法下降。在這樣的狀況下，橫膈收縮時會將下肋骨往頭側拉，使肋骨抬起並形成擴張的型態。如果肋骨被收緊的腹肌固定住，則呼吸動作將由上、中胸廓所代償。腹部的凹陷與腹壁僵硬的束縛對理想橫膈活化的發生將造成不良的影響。

Weak abdominals:  Abdominal weakness impairs the diaphragm function.  If the abdominal wall offers no resistance to the diaphragms contraction it would only displace itself downwards without any distinct increase in IAP. The opposition against the diaphragm contraction performed by the abdominal muscles maintains the important zone of apposition and dome shape of the diaphragm.

Hyper-tonic abdominals:  If the abdomen is held too firmly by the abdominal muscles the central tendon cannot descend. Instead, as the diaphragm contracts, it pulls cranially on the lower ribcage which elevates and expands the ribs. If the ribs are completely fixed in place by a strong abdominal muscle contraction the breath will entirely be performed with the upper and middle chest. Abdominal hollowing and a too rigid bracing of the abdominal muscles are therefore counterproductive for ideal diaphragm activation to occur.

10. 理想的腹肌

理想的腹肌運作維持腹腔的形狀與足夠的壓力，同時也提供橫膈足夠的活動，進而讓下肋更充分的擴張。理想的腹內壓是由橫膈、骨盆底肌以及腹壁肌肉協同的運作而維持產生的。吸氣時，離心收縮的腹肌在維持ZOA、橫膈與腹肌之間長度-張力比及軀幹的穩定性與支持都扮演關鍵的腳色。吐氣時，腹肌收縮會增加橫膈長度及圓頂形狀，讓吸氣動作更有效率。

運動時，腹壁肌肉在吐氣的最後階段被強烈徵招，強迫空氣排出肺臟。此強迫吐氣機制會在下次吸氣前增長橫膈膜的纖維，因此可以製造更多的張力來增加吸氣的容積。

Ideal abdominal activity maintains the shape and pressure of the abdominal cavity sufficiently to make the action of the diaphragm more expansive on the lower ribs. The required intra-abdominal pressure is created and maintained by the synchronized activity between the diaphragm, the pelvic floor and the abdominal wall. The eccentric contraction of the abdominal wall during inspiration plays a crucial part in maintaining the zone of apposition and the length to tension ratios between the diaphragm and the abdominal muscles, as well as creating stability and support for the trunk. During expiration, contraction of the abdominal muscles increases the length and dome shape of the diaphragm, allowing for an effective contraction during inspiration

When exercising, the muscles of the abdominal wall are often heavily recruited during late expiration to force air out of the lungs. This forced expiration lengthens the diaphragm fibres prior to the next inspiration contraction and the diaphragm is thereby able to generate more tension which will increase the inspiratory volume.

11. 失能的呼吸模式原因

發育上：出生後第一年不理想的發育會影響穩定系統且造成姿勢上的改變。發育異常影響呼吸的特徵包括:短小僵硬的胸腔（嬰兒胸）、腹斜肌鏈沒有活化足夠造成的下肋外翻、前凸且無力的腹肌常伴隨著腹直肌分離的現象。抬高的胸腔位置以及無力的腹肌大大的減少了橫膈的效能。

醫學上：呼氣末肺容積對橫膈膜收縮及肋骨有很大的影響。慢性阻塞性肺疾病（COPD)、肺氣腫、氣喘等問題常與肺部過度充氣有關（FRC functional residual capacity增加）。過度充氣會造成橫膈縮短、減少圓頂弧度及ZOA區域。研究顯示慢性肺部過度充氣造成橫膈尺寸上的改變，此現象特別發生在ZOA區域。

縮短的橫膈會減少它的力量與效能。橫膈連接下肋骨的纖維是水平走向的（低平橫膈）而非垂直走向。下肋骨走向也變得較水平而不是正常的斜向位置。在這個情況下，橫膈收縮將無法抬起與擴張下肋骨；反在吸氣時，會把下外側肋骨帶往內收。Hodges 研究顯示，呼吸疾病使橫膈與腹橫肌的共同作用功能減少。此外，心臟疾病也影響到呼吸模式。

情緒上：心理上與情緒上的狀態常常改變呼吸的控制。透視影像的研究顯示，在緊張的情況與情緒的壓力下，橫膈膜會呈現高張特徵，像是變得比較扁平與活動降低。

失能的呼吸特徵在一般人占11 % ；占氣喘族群30 %；焦慮族群高達83 %。

呼吸需求增加也會改變呼吸的模式。代償上，將減少呼吸肌肉的功能，轉而維持姿勢。

Causes of dysfunctional breathing patterns

Developmental:  non-ideal development during the first year of life affects the stabilization system and often results in postural changes. Signs of developmental abnormalities affecting respiration can be a short stiff chest (baby-chest), flaring of the lower ribs from insufficient activation of the oblique abdominal chains, and a protruding weak abdominal wall often with a diastasis of the abdominal wall present. The high chest position and weakness of the abdominal wall and markedly reduces the diaphragm’s efficiency.

Medical: The end expiratory volume of the lungs has a great influence on the power of the diaphragm contraction and its effect on the ribcage. Conditions like Chronic Obstructive Pulmonary Disease (COPD), emphysema and asthma are often associated with hyperinflation of the lungs where air gets trapped in the lungs. Hyperinflation results in a shortened diaphragm with decreased dome curvature and a reduction of the ZOA (3). Studies have demonstrated that changes in the diaphragm dimensions produced by chronic hyperinflation occur almost exclusively in the zone of apposition.

The shortening of the diaphragm decreases its power and efficiency. The diaphragm fibres attaching to the lower ribcage end up in a transverse orientation (low flat diaphragm) rather than vertical, and the lower ribs shift from their normal oblique position to a more horizontal direction. When the diaphragm contracts during such circumstances it is unable to lift and widen the lower ribcage and instead the lower lateral ribs are being pulled inwards during inspiration (Hoover’s sign (5)). Hodges et al (4) showed that during respiratory disease the co-ordinating function between the diaphragm and the transversus abdominis was reduced. Heart disease also commonly affects the breathing pattern.

Emotional: Psychological and emotional states often alter the respiratory control. Fluoroscopic studies show that in situations of tension and emotional stress the diaphragm shows signs of hyper-tonicity by becoming flattened and immobile.

Dysfunctional breathing is shown to be present in 11% of the normal population, in 30% of asthma sufferers and 83% in people suffering from anxiety (1).

Increased respiratory demand alters the breathing pattern and often reduces the respiratory muscles ability to perform their postural duties (4).

12. 其他正確的橫隔膜呼吸的好處

理想的橫膈呼吸讓橫膈能夠同時執行呼吸及產生足夠腹內壓以提供脊椎支持與穩定的雙功能。此外，橫膈呼吸可增加吸氣容積，促進了肺部通氣量，進而增加血液中含氧量。且下半部肺葉有更多的膨脹，讓更多血液進入下半部肺葉進行氣體交換。

橫膈吸氣會給予腹腔內器官機械效益。失能的呼吸則很淺，主要造成上半部肺葉膨脹。橫膈呼吸同時也提供足夠的腹內壓，藉此維持脊椎穩定。失能的呼吸模式中，呼吸輔助肌（頸部、胸部、背部）不會被徵召。(最後一句話好像怪怪的~)

Additional benefits from proper diaphragm breathing

As mentioned earlier, proper diaphragm breathing allows the diaphragm to perform its respiratory function while simultaneously providing stabilization support for the spine by an increased intra-abdominal pressure (core). Properly synchronized diaphragm breathing also improves the ventilation of the lungs by increasing the inspiratory volume, which increases the level of oxygenation of the blood since the lower lobes expand more, and the majority of the blood sent to the lungs goes to the lower parts.

There is a mechanical effect on the organs in the abdominal cavity when they get pushed downwards during diaphragmatic inspiration - Dysfunctional chest breathing is shallow and mainly expands the top part of the lungs. The posture improves when the lumbar spine properly supported by a sufficient IAP and no accessory muscles (neck, chest and back) are being recruited as in the dysfunctional breathing patterns.

總結

核心穩定的關鍵在於最大化橫膈同時執行呼吸與體態的維持的雙重效益。Kolar研究顯示橫膈在執行姿勢維持會比一般潮氣呼吸時，橫膈會更往下推入腹腔。當橫膈的姿勢維持需求增加時，橫膈在吐氣的位置會比一般呼吸要來得更低。簡單來說，橫膈可自主控制更往下推來增加腹內壓，提供腰椎穩定的支撐。藉由橫膈、骨盆底肌及所有的腹壁肌肉協同作用，來增加腹內壓且同時保持正常的呼吸，這才是核心穩定的真正關鍵。

橫膈在一個比較低的位置時可促進增加腹內壓，腹壁肌肉則提供對抗橫膈的力量。當吸氣時，橫膈收縮，腹部的肌肉會稍微離心收縮來對抗較高的腹內壓，吐氣時，腹肌向心收縮來代償因橫膈離心往上移動而減少的腹內壓力。腹壁肌肉對抗力量的機制可確保橫膈維持理想的長度及圓頂形狀，同時增加橫膈的效能。胸腔的位置及ZOA區域對橫膈的活化也有非常重要的影響。

所以，核心的穩定始於正確的啟動橫膈功能！

Summary

The key to core stabilization is to maximize the diaphragm’s efficiency in performing breathing activity and postural tasks at the same time. Kolar (7) (8) showed that the diaphragm pushes further down into the abdominal cavity during a postural task than during tidal breathing. When the postural tasks become more demanding the diaphragm’s expiratory position is lower than during tidal breathing. In short this means that the diaphragm can be pushed down voluntarily to increase the Intra-Abdominal Pressure (IAP), and provide stabilization support for the lumbar spine. The key to real core stabilization is to maintain the increased IAP while going through normal breathing cycles. This is achieved by the synchronized activity between the diaphragm, pelvic floor and the entire abdominal wall.

The diaphragm then performs its breathing function at a lower position to facilitate a higher IAP. The abdominal wall provides opposition to the diaphragm’s action. When the diaphragm contracts during inspiration the abdominal wall maintains the high IAP through an opposing and slightly eccentric contraction, and during expiration the actions are reversed and the abdominal muscles contract concentrically to compensate for the reduced pressure resulting from the diaphragm’s eccentric upward movement. The opposing activation of the abdominal wall increases the diaphragm’s efficiency of contraction by ensuring the optimal length and dome shape of the diaphragm is maintained.  The position of the chest and its effect on the zone of apposition is crucial for proper diaphragm activation.

Core stabilization starts with proper function of the diaphragm!