Amissing piece of the puzzle, the Mount Sinai teams soon found, was right in front of them: breathing. Everyone knew, of course, about severely sick COVID‑19 patients on ventilators. What the researchers and doctors at Mount Sinai hadn’t realized was that even mild cases might be affecting respiration after the acute phase of the disease.
Evidence began to accrue that long-COVID patients were breathing shallowly through their mouths and into their upper chest. By contrast, a proper breath happens in the nose and goes deep into the diaphragm; it stimulates the vagus nerve along the way, helping regulate heart rate and the nervous system.
Many of us breathe through our mouths, slightly compromising our respiration, but in patients with post-acute COVID syndrome, lung inflammation or another trigger appeared to have profoundly affected the process. In these cases, patients’ breathing “is just completely off,” McCarthy told me.
Over the summer months, Chen’s and Putrino’s teams refined their treatment approaches, observing and analyzing all the while. They addressed patients’ disparate symptoms (such as new food sensitivities, or roaming pain) with dietary changes, stress-management techniques, and individually tailored rehab.
In addition, they introduced a science-based breathwork program, designed by a new company called
Stasis, to try to restore normal breathing patterns in the sickest patients. Jessica Cohen used it over the summer to help recover from her setback. For Caitlin Barber, breathwork came in the fall, more than half a year into her ordeal.
One night in April, Josh Duntz woke up with an idea and scribbled “breathwork” in his bedside notebook. He reached out to David Putrino.
The Stasis program is deceptively simple and strikingly low-tech: It involves inhaling and exhaling through your nose in prescribed counts in the morning and at night.
The protocol was developed by Josh Duntz, a Navy Special Operations veteran, and his co-founder, Dan Valdo. During a decade in the Navy—he left in December 2019—Duntz had become obsessed with physical and mental performance under stress. “It was quite literally the difference between life and death,” he told me.
Trying breathwork himself after a workout partner introduced him to it, Duntz noticed immediate improvement in his endurance runs: He could run for longer with a lower heart rate, and without getting tired. He dug into the emerging science of breathing and became a convert.
By luck, Duntz knew Putrino; the two had been working together on a project prior to the pandemic. In the spring, he heard about the persistent breathing problems of COVID long-haulers.
One night in April, he woke up with an idea and scribbled “breathwork” in his bedside notebook. “So I reached out to David to say, ‘I think this could work and here’s why.’ ” A piece had clicked into place for Duntz: Similar symptoms (fatigue, shortness of breath, racing heart) occur in people who have low carbon-dioxide levels in their blood—a condition known as hypocapnia, which can be triggered by hyperventilation, or shallow, rapid breathing through the mouth.
Duntz wondered if perhaps these long-COVID patients, so many of whom suffered from dizziness and tachycardia, were also breathing shallowly, because of either lung inflammation even in mild cases or viral damage to the vagus nerve. The theory seemed plausible to Putrino: Oxygen is key to our health, but carbon dioxide plays an equally crucial role, by balancing the blood’s pH level.
Mount Sinai was able to launch a breathwork pilot program swiftly because of “how desperate people were—the hospital was so overwhelmed,” Duntz said. The program also didn’t have to pass FDA clearance.
After a week, everyone in the pilot program reported improvement in symptoms like shortness of breath and fatigue. (No double-blind randomized controlled trial has yet been conducted, so it is not possible to know what percentage of the improvement was due to the placebo effect.) The patients’ responses were “game-changing,” Putrino told me.
The key was the realization that the diaphragm and the nervous system had to be coached back to normal function before further reconditioning could start. “You cannot rehabilitate someone when their symptoms are completely out of control,” Putrino said. Although patients still faced an unfolding array of unpredictable symptoms, breathwork helped get them to a “place where the healing can start.”
That was Barber’s experience. In early November, seven months after getting sick, she began doing the breathwork with her husband, inhaling through the nose for four counts and exhaling for six in the morning, and in the evening, inhaling for four, holding for four, and exhaling for four. (I tried these routines and found them surprisingly hard.) She immediately discovered that she could better calm herself during an episode when her heart began racing.
Dayna McCarthy at the Center for Post-COVID Care laid out the group’s theories about why the treatment is so helpful. Through breathwork, patients can consciously control their heart rate, she noted.
In addition, modulating the nervous system’s fight-or-flight response may help regulate the immune system. (Studies have shown that elevated stress hormones can lead to chronic inflammation.) And proper breathing is crucial to circulation in the lymphatic system, often described as the body’s highway for immune cells, which plays a role in eliminating toxins and waste.
I talked with Barber a few weeks after she started the breathwork. She had noticed a dramatic decline in her heart rate. “It doesn’t help with my mobility,” she said. But “for some reason, my symptoms”—of breathlessness, dizziness, and brain fog—“have noticeably lessened.” She had her period the week we talked, usually a time when her symptoms intensified, but that month they hadn’t.