Bonnie Tsui's Latest Book Uncovers What It Truly Means to Be Strong

Not far into her latest work exploring the vast and intricate role of muscles, writer Bonnie Tsui includes the passage, “As a kid, I learned to do handstands from my dad; as an adult, I began doing headstands as a regular practice in yoga. If I ask myself why I still do them, I realize that I like going upside down because it not only encourages a radical shift in body awareness, but also in perspective.”

That innate curiosity remains evident throughout her book On Muscle: The Stuff That Moves Us and Why It Matters. In her characteristic manner, Tsui intermingles science writing, personal essay, and philosophical musings as she relates the nuanced manner in which muscles influence our perception of life. In the following excerpt, she shares what she learned from adaptable yoga teacher Matthew Sanford as he leads class from a wheelchair. Through her experience, she explores thought-provoking insights that can—and should—expand our understanding of the larger practice of yoga. —Renee Marie Schettler

Consider the word yoga. In Sanskrit, it means “to yoke,” to dissolve separation between body, mind, and breath. In its ideal form, the practice is all about connection, and about being more aware of your body—to know it better and to recognize the parts you routinely ignore.

Matthew Sanford is a pioneer in adapting yoga for people with disabilities, like spinal cord and brain injuries, multiple sclerosis, ALS, muscular dystrophy, and cerebral palsy. Like many of his students, Matthew uses a wheelchair. But yoga taught him to resist the convention in the medical world to forget the parts of his body that were paralyzed; instead, he sought synthesis. He describes the practice of yoga as putting muscular action in service to the whole.

Periodic disconnection is something each and every one of us experiences, Matthew says—whether we’re paralyzed or not, and often on a daily basis. “Think of the contrast between slouching in your chair—with your sit bones like butter, your legs and lower back are dulled—and sitting up straight, at the edge of your chair, with your sit bones like knives,” he explains, by way of example.

Instinctively, I find myself straightening up and scooting my butt to the edge of my seat.

“When your feet are on the floor and your head is stacked above your spine, your legs wake up—they are more alert,” he says. “So are mine!” I watch as he repositions his legs with his hands. “There is connectivity to be found in alignment and precision, and in grounding the body—and that’s especially important to the disabled body.”

Yoga requires you to sit in the presence of the body you have. To feel more, and to feel more whole. In its practice, you are choosing—every time—to begin anew, to reestablish your body in the world.

Asana, he says, helps restore shape to every body. When you put yourself into a pose, you gain strength, flexibility, and balance. The popular Western conception of yoga involves a specific kind of flexibility: a Gumby-like body that can stretch and contort into otherworldly postures. But yoga, an ancient discipline tracing back thousands of years in India, is fundamentally about grounding the body in this world, now.

Yoga requires you to sit in the presence of the body you have. To feel more, and to feel more whole. In its practice, you are choosing—every time—to begin anew, to reestablish your body in the world.

Before I actually met Matthew in real life, I met him online, in his regular Monday morning yoga class. Matthew bounced in his wheelchair and smiled. He demonstrated lifting up off his seat on his hands, to create space in the spine and wake up the lower back and the legs. I followed the sensation of space in my spine down my legs to my feet. I flexed and stretched my toes and relished how good that small intricate unfolding felt. With Matthew’s direction, I paid closer attention to subtle changes, inside and out.

“As you stretch, don’t push through its resistance. Let it have its voice, and figure out how to become part of it,” he told us.

A couple of weeks later, I visit Matthew at home, and we have a yoga class of our own. With the help of his partner and fellow teacher, Molly Bachman, he demonstrates some of the ways that the principles of yoga can be applied to bodies of differing abilities. One of the more remarkable poses they show me is a modified handstand.

We reposition ourselves flat on our backs on the floor, bodies perpendicular to the base of the wall and our heads at arm’s length from it. “Reach your arms up behind you, place your hands flat on the wall, and look where you’re reaching,” Matthew instructs.

The effect is startling: the stretch of the muscles along my arms, ribs, and abdominals, the arch of my back and neck, the feeling of reaching and reorienting the spine, the grounding of hands in the “earth”—in this case, the foundation was the wall—all culminate in the feeling of going upside down onto my hands, just with a little less gravity. It speaks to the flexibility of muscles and the brain to receive the benefits of yoga.

When I start digging into research journals, I discover that what Matthew talks about as presence, grounding, and reestablishing the boundaries of the body in yoga practice after spinal cord injuries has only recently begun to be described in scientific language. Peripersonal space representation: This is an unwieldy term, but it includes information gathered through proprioception and interoception, and visual and other bodily signals.

Proprioception, your body’s ability to sense itself in space, is how you stay upright, balanced, and moving safely through the world without thinking about it too hard. Generally speaking, external receptors in your muscles, skin, and joints send messages to your brain. Interoception is your body’s ability to sense itself from inside. It encompasses how your body feels. Internal receptors in your organs, bones, and blood, and also your muscles transmit molecular, biochemical, and electromagnetic information, often below the level of consciousness, to help the body maintain homeostasis.

A functional sense of the body in space is diminished for someone who is paralyzed through injury or disease, because voluntary movement and surface sensation is limited. But a lot of awareness can be restored through the mobilization of affected limbs—as with, say, a yoga practice. A recent study with paraplegic and control subjects shows that motor feedback, not just visual cues, is critical to the recovery of healthy peripersonal space representation. Cognitive functions such as the representation of space, the researchers wrote, “are grounded in sensory-motor functions and bodily signals.”

The science is so new that the mechanisms underlying this recovery are unclear. What is clear, however, is that moving the physical body itself, both actively and passively, helps to integrate signals for presence.

This excerpt is from Bonnie Tsui’s new book, On Muscle: The Stuff That Moves Us and Why It Matters, which will be published on April 22 by Algonquin Books.