What Is the Vagus Nerve, and What Does It Do?

What do you think of when you think of yoga? Really supple people bending themselves into impossible shapes? Incense-filled rooms with rows of people lying down with their eyes closed? A gong? Is yoga slow and stretchy to you, or hot and hard? Plain and simple, or a complex mix of movement and Sanskrit?

The point is, yoga isn’t really one thing. It consists of multiple styles. Each instructor brings their own flair, wisdom, and understanding to each class. And it takes place in every imaginable setting.

Whatever you think yoga is, there will be an example out there to prove you right. But if you say “yoga is not for me”, you are almost certainly wrong.

While yoga is an ancient practice, it has many practical applications and benefits for the modern world. There are three ways yoga can support your daily life.

Yoga is a good exercise

Yoga’s physical exercises are called asanas. Asanas help develop strength, muscular and cardiovascular endurance, stability, and flexibility. Regular practise develops power, speed, agility, coordination, and balance. As a result, yoga can improve your heart and musculoskeletal health, protect against injury, and improve sports performance.

Like all forms of exercise, yoga boosts endorphins (feel-good hormones) and reduces cortisol and adrenaline (stress hormones). It also improves brain function by promoting the growth of new brain cells (neurogenesis), increasing blood flow, and boosting connections between neural networks in your nervous system (neural connectivity).

Yoga promotes healthy breathing

In yoga, movement is linked with breath (pranayama), and deep breathing is encouraged. Deeper breathing brings more oxygen to your muscles, enabling them to work more effectively. It also fuels your brain, helping to maintain focus. Controlled deep breathing also activates the rest-and-digest part of your nervous system (parasympathetic nervous system), shifting your body into calm mode and promoting better nervous system regulation.

The breathing you practice during yoga sessions can move into your everyday life. Deeper, more efficient breathing becomes second nature, and, when feeling overwhelmed, you are more likely to turn to breathing to restore calm and regain a sense of control.

Yoga is relaxing

While many types of yoga are far from relaxing, savasana (relaxation) is a core principle in yoga because the ability to rest and recover is essential to living a balanced life.

Rest is necessary for our brains and bodies to repair and rebuild. Resting refills our batteries and calms our minds, enabling us to refocus on what’s important and giving us the energy to achieve our goals.

In today’s fast-paced world of constant stimulation and pressure to achieve, many of us need to learn how to relax. Regardless of style or purpose, most yoga classes will end with a period of savasana, whether it’s just a couple of minutes of quiet time or a longer period of guided meditation.

This often feels strange or difficult to begin with, especially if you have ADHD, are a fidgeter, or tend towards constant busyness. But like all skills, we improve with practice. And savasana is not about clearing or ignoring our thoughts; its purpose is physical rest, nervous system rejuvenation, and the observation of thoughts without dwelling on them.

Yoga can be a space for simply being present, without the pressure to ‘do’.

Finding the right style

First, look for a class, in person or online, that fits your goals and personality.

If you like challenges and want to make big fitness gains, try Vinyasa, Flow, Ashtanga, or Power yoga. These classes will include exercises such as push-ups, arm balances, and explosive movement to build strength and power, and allow only minimal rest to increase your heart rate and build stamina. These classes can be as physically challenging as CrossFit or HIIT.

If you want to learn the fundamentals of yoga and get an all-round workout, plus some relaxation, look for Hatha yoga. Hatha classes are accessible to all levels and usually include strength, balance, and flexibility.

If you are a bit of a perfectionist or like to delve deep into the technical aspects of things, try Iyengar classes, where the focus is on alignment, with lots of detailed cueing and props to help you achieve the best version of each position. Iyengar can also be helpful if you have an injury or chronic condition, as it’s unlikely you will push too hard and make it worse.

If you love to sweat, Hot or Bikram yoga is done in a heated room. This style warms the muscles and connective tissues for deeper stretches. It also increases your heart rate, bringing great cardiovascular benefits.

If you’re looking to focus on activating your parasympathetic nervous system, seek out restorative classes. Restorative yoga encourages passivity and stillness, relying on soft props (bolsters and blankets) to reduce the physical exertion needed to achieve poses.

Finally, Yin yoga is a slow-paced class where poses are held for several minutes. This targets deep connective tissues, improving flexibility and circulation. The challenge of Yin yoga is both physical and mental: holding yourself at the edge of discomfort while avoiding fidgeting or distraction.

Giving it a go

Yoga is for you. You only have to spend some time finding the style, teacher, and community that appeal to you.

Do you want a relaxed atmosphere where students and teachers interact during class, or do you prefer a silent practice to allow you to focus only on yourself? Are you open to the spiritual side of yoga, or is it all about the science of the exercises?

Before joining a class, check out the instructor or studio’s website and social media, and don’t be afraid to contact them for clarity on what’s on offer. Online classes and apps are a great way to explore different styles, and they give you the flexibility of practicing when and for how long you want.

yōjō offers simple movement activities on our app. They only take a few minutes, are mostly drawn from yoga, and can be the perfect way to start experiencing its benefits.

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A few days ago, we passed the 12,500 VNS sessions mark. That’s 12,500 pre-session face scans, 12,500 VNS sessions, and 12,500 post-session face scans. That is a lot of data. And here’s what it’s telling us so far.

30 minutes of yōjō = 90 minutes of meditation

A single yōjō vagus nerve stimulation (VNS) session lifts heart rate variability (HRV) by 3.76 ms on average. In a study published in 2025, 90 minutes of meditation lifted participants’ heart rate variability by 4.68 ms.

Both practices produce real physiological change. They share the same target: parasympathetic activation and increased vagal tone. We’re comparing them with sustainability in mind. For most working professionals, 30 minutes of hands-free VNS might be easier to manage than 90 minutes of meditation.

HRV improvement compounds

On average, yōjōers see a 1.5% improvement in HRV from established baselines after 1 month. That doesn’t sound like much, but the rate of change increases over time.

Month 1 — HRV up 1.5% from baselineMonth 3 — HRV up 4.7% from the baseline set in Month 2Month 6 — HRV up 16.5% from the baseline set in Month 5

Nervous systems respond better the more you train them.

yōjōers have a favorite mode

Of all these thousands of sessions, 49% were done in the Stress Mode. Sleep Mode came in second with 27%.

We’ve also seen a healthy spirit of exploration. Most of our members try all modes before eventually settling on one.

Why this matters

This shows that daily vagus nerve stimulation effectively supports nervous system health. It also proves that technology that was only a few years ago confined to the clinical setting can, in fact, fit into real life.

And it proves that yōjō’s device + human coaching + gentle data tracking boosts adherence, helping people stimulate their vagus nerve every day (more than once a day on average, based on the data).

Everything we’re learning — how our members yōjō, why they yōjō, what yōjōers need from their device, coach, or platform — is going into yōjō experience and making a bigger positive impact.

Much of it has already helped refine the yōjō Stone, our latest device, launching towards the end of the year.

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A few months ago, the gROW Atlantic Team, Vicki Anstey and Dr. Sophie Bostock, asked us a simple question: could yōjō help the team not only survive crossing the Atlantic in a row boat but make it across faster than any other female team?

We said we think so, let’s see.

This December, Vicki and Sophie will join the World's Toughest Row 2026: a 3,000-mile rowing race starting in San Sebastian, La Gomera, Canary Islands and ending at Nelson's Dockyard, Antigua. They're aiming to break the current world record for a female pair — 38 days and 12 hours — rowing two hours on, two hours off, for an estimated 1.5 million oar strokes.

They’ll face storms, salt, and silence. Sleep deprived and alone, they’ll have no support boat alongside them, no shore team, and no shortcuts — just two athletes, an ocean, and whatever they have brought with them, which happens to include their yōjōs, because peak performance, rapid recovery, and sustained endurance come from a well-regulated and flexible nervous system.

Meet the record-breakers

Vicki is a world record-breaking adventurer, TEDx speaker, and a leading expert on resilience, mindset, and human performance. She is a Certified Stress & Resilience Coach, UK Ambassador for Inspiring Girls, and one of the first women finalists on Channel 4's SAS: Who Dares Wins. She holds two world records for rowing the Pacific Ocean unaided in 2021 and for cycling 3,000 miles across America in the 2024 Race Across America.

Sophie is a sleep scientist with a PhD, the founder of The Sleep Scientist, and a national authority on sleep, recovery, and the nervous system. She has worked with elite athletes, surgeons, military personnel, and Olympians on the science of rest, alertness, and resilience under pressure.

Between them, they hold decades of expertise in the exact systems yōjō exists to support: rest, recovery, regulation. Which is what makes this partnership feel so natural.

No strangers to nervous system health, Vicki and Sophie have been thinking about, teaching, and living autonomic flexibility long before they ever set foot in an ocean rowing boat.

What their bodies will face out there

It’s called the World’s Toughest Row for a reason.

More people have climbed Everest than have rowed across an ocean. For a two-person crew, the load is particularly unforgiving. There is no third pair of hands. If one of you is sick, injured, or simply exhausted, the other one rows.

To understand why this matters to us, it helps to understand what around 38 days of that environment does to a human nervous system.

The autonomic nervous system has two branches that work in balance. The sympathetic branch drives action, picking up heart rate, quickening breathing, elevating cortisol levels, and narrowing attention. The parasympathetic branch, carried largely by the vagus nerve, does the opposite. It slows the heart, deepens the breath, and shifts the body into the state where repair, digestion, and recovery happen.

In healthy daily life, these two branches alternate fluidly. You activate when you need to act. You recover when you don't. That flexibility — the ability to shift between drive and recovery on demand — is what we mean by autonomic balance, and it shows up in measurable signals like heart rate variability (HRV).

Ocean rowing collapses that flexibility.

Sleep is fragmented into 90-minute windows (usually less!), never allowing a full recovery cycle. Rowing through the night completely disrupts circadian rhythms. Cortisol stays elevated. Cold and salt exposure keep the sympathetic system primed. Caloric deficit and dehydration add further stress signals. The body, in short, is held in a state of near-continuous sympathetic activation for six weeks. Unfaltering stress.

When the dominant state will be one of stress, could parasympathetic support give Vicki and Sophie the snatches of recovery they need precisely when they need it?

Where we come in

yōjō exists for one reason: to help people maintain autonomic flexibility — the ease with which the nervous system shifts between drive and recovery. We do that by supporting parasympathetic activity through daily vagus nerve stimulation, human coaching, and data-driven personalized programs.

For Vicki and Sophie, who are about to test their nervous systems under conditions that compress years’ worth of physiological stress into 6 weeks, yōjō will be providing on-the-go access to their parasympathetic systems and a way to boost nervous system recovery through the full arc of this journey.

That means yōjō devices on board, with daily vagus nerve stimulation built into their training and racing routines. It means personalized protocols, tuned to each athlete's physiology, training load, and recovery profile. It means ongoing science support, from prep to finish, our science team reviewing data, iterating protocols, and answering the questions that come up along the way.

This is the cleanest possible expression of the science we build around. Helping two of the most physiologically literate athletes access recovery under conditions designed to deny it to them is precisely what yōjō is here to do.

Follow along

This is the start of an eight-month journey that will end on a beach in Antigua in early 2027. Between now and then, we'll be sharing the science, the milestones, and the data from Sophie and Vicki’s first training rows to their return to life after the race, and will be digging much deeper for a three-part documentary series called Do you, better.

If you want to follow along on LinkedIn and Instagram, we'd love to have you.