Most people have heard of the physical benefits of yoga. The word means "union" in Sanskrit, and the ancient practice of combining breathing and physical postures builds core strength, flexibility and alignment. As a fitness activity, yoga is comfortably in the mainstream now, with more than 25,000 yoga (and Pilates) studios in the United States as of 2014, according to an IBISWorld report.

With studios in every corner of the state, Vermonters are clearly on the bandwagon. In Burlington alone, nearly a dozen venues offer hundreds of classes per week in manifold yogic lineages. The sight of a person strolling down Church Street with a rolled-up mat is as unremarkable as that of a snowboarder headed for the mountain.

Our full understanding of yoga's benefits is still evolving. But recent scientific studies confirm what yogis have been saying for more than 2,000 years: The practice can calm and soothe the mind as well as strengthen the body. Those therapeutic properties have led to a new emphasis on yoga for mental health — and some practitioners are taking the principle further, offering yoga as a prescription for trauma.

"It's a stealth thing," jokes Bob Luce, a longtime yoga teacher at Burlington's Tapna Studio and an attorney at Downs Rachlin Martin. Tapna specializes in Bikram, a style of yoga in which students progress through a set series of 26 postures in sweat-inducing heated rooms. "We get them in the door with this promise of fitness, but what they really get delivered is so much more," Luce says.

While some students may use downward dogs to lift the spirits, others come with graver issues. Some local yoga practitioners have begun offering workshops and private sessions to mitigate the mental, emotional and physical effects of trauma. They address potentially crippling symptoms — depression, anxiety, substance abuse, insomnia — that are generally relegated to psychiatry and other mental health treatments.

"This is yoga in service of healing," says Deb Sherrer, a yoga instructor at Laughing River Yoga in Burlington and a psychotherapist at the Vermont Center for Integrative Therapy in South Burlington, where she also teaches trauma-sensitive yoga to clients. "It's very gentle. It's very slow. And it's yoga in the broadest sense, in that this is all about self-care," she says. "This is about tuning in to your body, reconnecting and listening to what it needs."

Sherrer works with individual clients and leads groups for women who have been victims of trauma. Trauma-sensitive yoga differs from regular classes, she explains. While students in the latter are generally encouraged to keep pace with the instructor, "one of the basic tenets of trauma-sensitive yoga is that you're given complete permission to do what you need to do," Sherrer notes. "The whole situation is set up based on safety."

Simple flow sequences, such as undulating the spine between cat and cow poses, are favored over more active and stimulating sequences. The goal is to use yoga to help people regain a degree of ownership and control over parts of their bodies where they have experienced trauma — whether caused by an assault, an accident or life in a war zone.

The principles of trauma-sensitive yoga were developed at the Trauma Center at the Justice Resource Institute (JRI) in Brookline, Mass., where Sherrer received her certification in 2009. That's where clinical psychologist Bessel van der Kolk, an internationally recognized expert in psychological trauma, conducted groundbreaking studies with trauma victims.

Though post-traumatic stress disorder has generally been considered a mental health issue, a growing body of research indicates that trauma also has profoundly physical effects. In a 2014 study of yoga as an "adjunctive" treatment for women with PTSD, researchers found that sufferers experience a "loss of body awareness" that makes it difficult for them to control emotional reactions to external stimuli. Symptoms such as panic attacks trigger the sympathetic nervous system, which stimulates the fight-or-flight response, Sherrer notes.

Some scientists suggest those findings point to the value of somatic, or body-centric, treatments for PTSD sufferers, along with appropriate medication and talk therapy. (Insurance nonetheless doesn't cover therapeutic yoga.)

"Psychiatrists just don't pay much attention to sensate experience at all," JRI's van der Kolk told journalist Krista Tippett in a 2013 appearance on her public-radio show "On Being." A well-rounded treatment, he argued, ought to acknowledge the physical nature of trauma and its symptoms.

"If people are in a constant state of heartbreak and gut wrench, they do everything to shut down those feelings to their body," van der Kolk told Tippett. "One way of doing it is taking drugs and alcohol, and the other thing is that you can just shut down your emotional awareness of your body."

That's where yoga — and other mind-body activities such as tai chi and qigong — comes in. Preliminary studies at the Trauma Center and elsewhere indicate that yoga's physical effect on the body is almost diametrically opposed to that of trauma. Yoga promotes mindfulness and calmer states, which counteract the fight-or-flight impulse and make it easier for one to control one's reaction to triggers. Overall, as van der Kolk and his colleagues concluded in the 2014 study, yoga can help "improve the functioning of traumatized individuals by helping them to tolerate physical and sensory experiences associated with fear and helplessness, and to increase emotional awareness and affect tolerance."

Sherrer concurs with that assessment. "Trauma is something that affects our whole being — it's not just in our minds," she says. "Trauma, by its nature, is an extraordinary experience that overwhelms someone's regular coping mechanisms, and then, when it gets stuck in their system, ends up resulting in this host of symptoms that we think of as PTSD."

How those symptoms look depends on the individual, therapists caution. Laura Gibson, director of behavioral health at the Burlington Lakeside Community Based Outpatient Clinic, works with military veterans who suffer from PTSD. The disorder tends to manifest differently in each patient, she notes, though some patterns do appear.

"What I see a lot in the veteran population is hypervigilance," Gibson says. "They are very much on guard; they feel like they can't get a grasp or feel in control. They're constantly scanning for danger, looking at the rooftops or down alleyways."

Gibson, who joined the clinic in 2009, believes yoga is an important lifestyle and wellness tool, and a good complement to the range of treatments the Veterans Health Administration provides.

For the past few years, the Burlington Lakeside clinic has offered trauma-sensitive yoga classes (free for veterans) with Suzanne Boyd. The Huntington-based yoga practitioner is a military wife whose husband was twice deployed to Afghanistan. Boyd says she was compelled to get her yoga-teacher certification after her own practice helped her cope with her husband's second stint in a war zone.

"I knew from my own experience, with how yoga helped me manage depression, that it could be a valuable resource for people," Boyd says. "As I was going through the stress of having my husband deployed, I was seeing other families I know, spouses and children, going through the same stress. I knew it was something I could offer and tell other family members about that wasn't expensive."

One veteran, who wishes to remain anonymous, tells Seven Days that he suffered from depression following his retirement from the Navy, with which he had numerous deployments. The veteran, who also has bipolar disorder, says of Boyd's class, "Once a week, I get to do something positive for myself. They do a lot of pre-relaxation, and then you concentrate on breathing and stretching ... It helps me to get centered again." In that centered place, he explains, "your mind is clear, and you're more in control of your emotions."

Gibson says Boyd's classes have been popular; for some students, she adds, the experience is transformative. "I've seen people who, when I first mentioned yoga, looked at me like I had six heads — like yoga was the last thing on Earth they'd ever try," she says. "But with some persistence and a sense of humor, they went and, once they tried it out, they were hooked."

As a lab technician in the Air Force, Heather Satterwhite never saw combat. Nevertheless, she says that some of her military training involved "anxiety-inducing techniques," and that doing yoga at the Lakeside clinic has "been great for deprogramming and slowing down."

Satterwhite adds, "I've noticed a significant reduction in stress and anxiety and a better ability to act in the moment."

It's not just veterans who suffer from PTSD. As Tapna Studio's Luce notes, just about everyone has experienced some kind of trauma: negative experiences during childhood, unhealthy relationships, car accidents, sports injuries. Many of us walk through life spending more time than we should in states of stress or fight-or-flight mode, even if those states aren't severe enough to result in a diagnosis.

As a Bikram teacher, Luce says he has noted that students struggling with depression or anxiety are attracted to the rigor, discipline and community that the activity offers. With high temperatures and challenging postures performed in front of a mirror, his classes leave little room for the mind to wander.

As a litigator, Luce specializes in civil lawsuits involving brain and spinal cord injuries. He's also president of the board of the nonprofit Brain Injury Association of Vermont. Both positions require him to be up on the latest brain science, and he's something of a local expert on traumatic brain injury (TBI).

That brain science, Luce says, shows yoga creating a positive feedback loop that contributes to recovery. Though yoga and mindfulness aren't for everyone, he acknowledges, some of his TBI clients have benefited from such practices designed to bring people into the present moment, tailored to their post-injury body and level of ability.

"I find that the single greatest impediment to recovery, whether from a brain injury or another kind of injury, is depression," Luce says. "It's being unable to give up focusing on what you've lost, on what you can't do, and to be in the present and redefine yourself in the present."

The aim of therapy is to help those who've suffered trauma interact with the world based on their current situation rather than a memory. To that end, "practices like yoga," Luce says, "happen to be an effective tool."

The original print version of this article was headlined "Just Breathe"