When we talk about core power, abdominal muscles come to mind. But our core is much more than that. It connects us to our feelings and moods via the nerves of our gastrointestinal system and our enteric nervous system, or “belly brain.” We might feel off kilter when our gut health is out of whack or disconnected from life when our bellies are hard and tight. We can also experience upset stomachs when we feel stressed, depressed, or sleep-deprived.
Here’s a fuller view of your core, or the space between the diaphragm and pelvic floor, wrapping around the torso—also known as “the midsection” and “abdominopelvic cavity.”
- It includes numerous muscles, superficial and deep: rectus abdominis, internal and external obliques, transversus abdominis, multifidus, erector spinae, quadratus lumborum, and distal latissimus dorsi.
- It is home to most of your viscera: stomach, spleen, small and large intestines, liver, gall bladder, kidneys, pancreas, bladder, and reproductive organs.
Your core muscles help control your posture and body position. For instance, the rectus abdominis works primarily to stabilize your rib cage in relation to your pelvis. The transversus abdominis and multifidus work with the pelvic floor and diaphragm to stabilize your lumbar spine. Your core muscles also produce and transfer force during dynamic movements such as vinyasa yoga or running, maintaining spinal stability in order to protect your nerves, disks, joints, and connective tissue.
Box Breath Muscles
Among your core muscles, your abdominal muscles—rectus abdominis, internal and external obliques, transversus abdominis—work as accessory respiratory muscles, affecting how well you breathe, which, in turn, affects how you feel. Use this simple breath-based practice, which manipulates pressure in your belly space, to explore how changes in muscle activation affect your mental and emotional states.
- Sit or lie down with as much support as needed to feel comfortable.
- Inhale and exhale at your own pace for 6-10 rounds of breath, allowing the body to move with the breath.
- After at least 6 rounds of breath, exhale and pull the navel toward the spine without moving the pelvis or rib cage.
- Hold the navel in and take 4-6 rounds of breath, noting the depth and other sensations of the breath.
- Inhale, relax the abs, and breathe at your own pace until you feel recovered.
- Then, exhale and pull the lower abs in toward the sacrum without moving the pelvis or rib cage.
- Hold the lower belly in and take 4-6 rounds of breath, again noting the depth and sensations.
- Inhale, relax the abs, and allow yourself to recover.
- Finally, exhale and pull the side waist in toward the center of the body without any accessory movements.
- Hold the side waist in, like a tight wide belt, and take 4-6 rounds of breath.
- Inhale and breathe naturally, noting any changes in breath and body sensation.
Your sense of well-being relies deeply on the condition of your enteric nervous system, which connects to your central nervous system via the vagus nerve and several other pathways. The belly brain and central nervous system work together to control digestive function and how you react to stress. When your belly feels painful, acidic, or heavy, your nervous system and perception often mirror these qualities; you may find yourself sticking to a hard, narrow view, and have trouble adapting to change. In particular, stressors such as chronic disease, sleep deprivation, work-life imbalance, and emotional suffering stimulate the vagus nerve and changes in hormone levels, blood pressure, metabolism, and mental clarity.
Research shows the damaging effect of chronic stress on vagal tone, especially the correlation between an exaggerated stress response and gastrointestinal conditions like irritable bowel syndrome. Restorative Yoga is one way to allow your body to rest, digest, and repair itself. In particular, supported and restorative back extensions take pressure off the belly region by positioning it higher than the heart and head. Most of us remember a time when our gut feeling was so strong that it drowned out the voices in our head; practicing these back extensions lets us further develop our intuition. With our soft belly lifted, we open ourselves maximally to the present moment and might find clarity if we feel confused or conflicted. There is no greater position of vulnerability and strength.
Learning to trust your gut requires gentle, consistent practice. When you feel anxious, depressed, or fatigued, take at least 20 minutes to practice an extended-leg variation of Setu Bandha Sarvangasana. (This pose is contraindicated for pregnancy, diastasis recti, spinal conditions such as lumbar stenosis and spondylolisthesis, abnormal uterine bleeding (menorrhagia), and GERD.) Supported Bridge Pose can help release tight hip flexors and abdominal muscles. It may relieve anxiety and depression by taking energetic pressure off the brain, inviting the body to lead. And it can alleviate insomnia by giving the mind a back seat through lowering the head’s position relative to the heart and belly.
About our expert
Mary Richards has been practicing yoga for almost 30 years and travels around the country teaching anatomy, physiology, and kinesiology. Mary, a hard-core movement nerd and former NCAA athlete, has a master’s degree in yoga therapy. Learn more at maryrichardsyoga.com.