My Second-Favorite Muscle

My first favorite muscle is the heart.

I have recently developed a second favorite muscle, and it’s a good one. It helps our heart with circulation and consciously controlling it can affect mood. Can you guess what it is? Here are your clues: It’s structure is related to the bottoms of your feet, the roof of your mouth, palms of your hands, and the containing wall at the base our pelvis that you might be sitting on right now. When it contracts it pulls down and spreads open. When it relaxes it comes to rest in a dome-shape. Do you know what it is yet? It massages our heart, opens our lungs, is attached to our liver, and separates our chest from our abdomen.

That’s right! it’s the thoracic diaphragm, also known as the breathing diaghragm. The word comes from Greek, and generally means a partition or separating layer. The diaphram is a double-dome sitting horizontally between your chest and abdominal cavity. Some imagery is an umbrella, a mushroom, and a bellows. It attaches to the bottom of our ribs, including the tips of the floating ribs way out in the sides. In the back, it attaches to the front of the lumbar spine and the tendon runs down and joins the container of the pelvic floor. In the front, it attaches to the the xyphoid process, the little tip at the bottom of your sternum or breast bone, the plate of bone in the center of your chest where your ribs attach. You can feel for these bones and find your diaphragm, it’s easy to feel because it’s moving as you breathe. I invite you to gently trace along the bottom angle of your ribs with your fingers to bring some awareness to this tissue.

You can start in the front by finding your breast bone. It’s kind of bumpy, move your fingers down to the tip, that ‘s the xyphoid, it feels a little funy to touch sometimes so be gentle. Pause and notice, does it move as you breathe in and out? Continue to trace along the bottom of the ribs. Let your fingers sink into the soft tissue just below the lumpiness of your ribs. Balance your attention between your fingers and the parts that you’re touching. Soften into the tissue by using gentle, soft fingers. Keep going around the sides, it can be tender here where the rib tips are free floating and not attached in front. Keep going around to the back and feel where the bottom ribs meet the spine. If you can reach, use your thumbs and soften into the tissue between your lumbar vertebra. The lumbar vertebra are wider than the thoracic, so that’s how you know you’re on them, and the diaphragm attaches between the first and second lumbar. The muscles are big here and it usually feels good to touch. You’ve just touched the attachments for the diaphragm. Now rest and take a few breaths.

Notice where your breath flows naturally. Placing a hand on your belly can help. Does your belly go out on the inhale? Good, let it be soft. Now, can you let the breath sink, so that instead of pushing out, your belly is still soft, but it feels like the air fills into your low back? Nice. Don’t worry if it takes a bit of practice to find this feeling. You might experiment with changing position. How does it feel to breath laying on your back? On your front? On the sides? If you’re on a hard(ish) surface, the resistance of the floor will change how you experience the spreading and opening of your rib cage.

If someone has recommended “diaphragmatic breathing” or “belly breaths,” they mean the ability of the diaphragm to lower towards the abdominal cavity to allow full expansion of your lungs. This requires decreasing tension in the abdomen and chest, becasue superficial muscles will restrict the use of this way cool muscle. Often, we stiffen in the centers of our bodies. Sometimes low back tension arches our spine and causes our organs to spill forward, so we tighten our bellies to keep it all in. Or we have learned to tuck our tail, or pull our bellies in for lots of reasons. Maybe we’re trying to have good posture, or unconscious responses to fear or stress is causing stiffness, tension, lack of sensation. Maybe throughout this exploration you have noticed your chest is flat and head forward, or upper shoulders so stiff you can’t really breath into the upper spaces of your lungs. It’s all a good starting place. If we find support for movement, we don’t need to hold and put forth so much effort. The diaphragm is one way I’ve found to offer my body support to reduce unecessary effort and find comfortable relaxed breathing.

This is a good start and you’ve already got a lot to practice. Come back to this another time if that feels like enough for today. It’s fun to get to know your breath. It’s always there, connecting us to the world around us in this constant exchange. And when you’re ready, we’ve got a lot more to explore!

As you inhale, the diaphragm is pulled down by central tendons that attaches to the front of the low back. Because the right and left domes are attached to the ends of the ribs, this causes them to widen. This opens the cavity that contains the lungs, which, unlinke the heart, are not muscle, but extremely flexible and stretchy tissue. Other muscles help to open the lungs as well. Serrated muscles help to spread the ribs apart, like fingers, and neck muscles help to lift the ribs in the front to make room in all 3 dimensions for the air exchange inside of your lungs.

Use your breath to find these structures and movements from the inside. Find the downward pull of the diaphgram on the inhale, relaxing back up on the exhale. Touch your ribs on the front, sides, back, and notice the feedback from the floor or chair you’re resting into. Feel into this 3 dimensional breathing space.

At this point, with all of our directed attention on inhaling with the the diaphragm and spreading the ribs, your breath may have gotten kind of forceful. It’s okay, it’s all very interesting and you might notice that this exploration is exciting. Balance that by practicing a full exhale and notice that, too. Practice an effortless inhale and complete exhale, squeezing all the air out. Generally, inhaling is stimulating, and exhaling is relaxing. Do you notice these changes in your state of arousal? Now let the breath travel wherever it goes, effortlessly flowing like a river.

The structures of the lungs are delicate. It is good for them to stay soft and stretchy. You might imagine your ribs not as firm and cage-like, but like elastic fingers that gently hold, squeeze and massage this inner fluid and air-filled world. The lungs have gossamer upside-down trees where blood cells exchange carbon dioxide for oxygen. It’s always good to remember that inside of you is very wet. We can tune into the fluid environment of the cells of the lungs to bring softeness and flexibility back into the tissues. The lungs have an intimate relationship with the heart. They sit on each side of the heart like two teddy bears, giving it a hug with each inhale. During the pandemic, Bonnie Bainbridge-Cohen released videos on cellular breathing of the lungs. Her approach to movement and awareness is called Body-Mind Centering©. You can find Bonnie’s somatizations of the lungs and other wonderful material on youtube if you’d like to explore this more.

The connective tissue that wraps around the heart, cushions and protects it, is continuous with the diaphragm. The heart sits into the little divet in the dome where the tendon is. Each time the diaphragm descends, it pulls away from the heart, and massages it upon it’s return. Can you feel that little tug on your heart as you inhale? Can you feel the heart rest into the support of your diaphragm and lungs? It’s really cradled in there, tenderly. The wraping around the heart protects it and provides it with spaciousness. The diaphragm properly opening and moving up and down helps the heart to circulate blood. It especially helps with the return flow by amplifying the pump away from the heart. The movement of the diaphragm is critical not just for the proper function of the lungs but for ciruclation of the blood as well.

What is below the diaphragm? The abdominal cavity is full of organs. This area where we process and transorm food needs movement and heat to do this important job. The movement of the diaphragm massages the organs, adding healthy internal movement. But, it can also support our voluntary movements. One large organ specifically is attached to the diaphragm through fascia connections, and that is the liver. The liver is a large organ that you can feel by placing your hands on your upper abdomen, it fills the entire right side going all the way to the center. Something to understand about organs is that they feel like water ballons. They have qualities of water, with heft and bouyancy. You can feel what it is to move your liver around, shift your weight a bit, feel it with your hand. And you can feel the connective tissue between the diaphragm and liver by feeling for a slippery and sliding quality between the two. Go ahead, slide the layers against one another. Move side to side, rotate a little. Can you move your diaphragm over your liver? Can you move your liver against our diaphragm? Here comes my favorite part. As the diaphragm goes down, feel how it pushes against the liver. I imagine a swimmer hoisting themselves up onto the edge of the pool. Like the diaphragm has tiny arms and lifts up off of the big platform of the liver. Explore how this movement can help to lift our body. It helps me to also feel the support of the ribs and thoracic spine like a sling. Move around a little, explore getting up from seated using this hoisting of the diaphragm and liver. Isn’t that fun?

I like playing with the diaphragm for all of these benefits. It helps to keep the body wide in all directions, opening space for breathing and for the organs of digestion. It helps me feel supported in the vertical plane. It helps me to decompress my spine and torso, and integrate the two body cavities. This horizontal muscle is so cool! I hope you will enjoy playing with these suggestions and find what is true inside of your own body.