11 science-backed ways to improve health, happiness, healing, relaxation, and mental clarity.

Vagus nerve is the main parasympathetic nervous system component.

It helps us rest and digest by slowing and stabilizing a resting heart rate, slowing and stabilizing the breath, promoting digestion, improving recovery and healing times, producing saliva, releasing endorphins and hormones like dopamine, oxytocin, and serotonin, and boosting the immune, digestive, and cardiovascular systems.

The vagus nerve sends anti-inflammatory signals to other parts of the body and is located behind the tongue, in the throat, neck, heart, lungs, abdomen, and brainstem.

Vagus means wandering in Latin. So, it's bold.

Here are 11 proven ways to boost health, happiness, and the vagus nerve.

1. Extend

“Yoga stimulates different nerves in your body, especially the vagus nerve that carries information from the brain to most of the body’s major organs, slows everything down and allows self-regulation. It’s the nerve that is associated with the parasympathetic system and emotions like love, joy, and compassion.” — Deepak Chopra

Stretching doesn't require a yoga background.

Listen to your body and ease into simple poses. This connects the mind and body.

If you're new to yoga or don't have access to an in-person class, try Yoga with Adrienne. Over 600 YouTube videos give her plenty of material.

2. Inhale

Because inhaling and exhaling activate the autonomic nervous system, we can breathe to relax.

Exhaling activates the parasympathetic nervous system (rest and digest). One inhales stress, the other exhales it.

So, faster or more intense breathing increases stress. Slower breathing relaxes us.

Breathe slowly, smoothly, and less.

Rhythmic breathing helps me relax.

What to do is as follows:

1. Take 4 smooth, forceless nose breaths.

2. Exhale smoothly and forcefully for 4 seconds

3. Don't pause at the inhale or exhale.

4. Continue for 5 minutes/40 breaths

5. Hold your breath as long as comfortable.

6. Breathe normally.

If four seconds is too long, try breathing in and out for two seconds, or in and out for three seconds, until your breath naturally relaxes. Once calmer, extend your breath.

Any consistent rhythm without force is good. Your heart will follow your lead and become coherent.

3. Chant/Hum

Singing, chanting, or humming activate the vagus nerve through the back of the throat.

Humming emits nitric oxide.

Nitric oxide improves blood circulation, blood flow, heart health, and blood pressure.

Antiviral, antibacterial, anti-inflammatory, antioxidant, and antimicrobial properties kill viruses and bacteria in the nose and throat.

Gargling water stimulates the vagus nerve.

Simple ways to heal, boost energy, and boost mood are often the healthiest. They're free and can be done anywhere.

4. Have more fun

Laughing stimulates the throat muscles, activating the vagus nerve. What's not to like? It releases dopamine.

Take time to enjoy life. Maybe it's a book, podcast, movie, socializing with friends, or laughing yoga.

Follow your bliss, as Joseph Campbell says.

Laugh at yourself

Actually. Really.

Gagging activates vagus nerve-connected muscles. Some doctors use the gag reflex to test the vagus nerve.

Grossness isn't required. While brushing, gag quickly. My girlfriend's brother always does it.

I'm done brushing when I gag, he says.

6. Take in the outdoors

Nature relaxes body and mind. Better if you can walk barefoot.

Earthing is associated with hippies dancing in daisies.

Science now supports hippies.

7. Enter some chilly water.

The diving reflex activates the vagus nerve when exposed to cold water.

The diving reflex involves holding your breath in cold water. Cold showers work best.

Within minutes of being in cold water, parasympathetic nervous system activity, which calms the body, increases.

8. Workout

Exercise increases dopamine, blood circulation, and breathing. So we feel energized, calm, and well-rested.

After resting, the parasympathetic nervous system engages.

It's worth waiting for, though.

9. Play music with brainwaves

Brainwave music harmonizes brainwave activity, boosts productivity and mental clarity, and promotes peace and relaxation by stimulating the vagus nerve.

Simply play a song.

My favorite.

10. Make gentle eyes

Eyes, like breath, often reflect inner state. Sharp, dilated, focused eyes indicate alertness.

Soft, open eyes reflect relaxation and ease. Soft eyes relax the nervous system.

This practice reduces stress, anxiety, and body tension. It's a quick and effective way to enter a calm, peaceful state.

Wild animals can be hunted one minute and graze the next.

Put it into action:

Relax while seated.

Gaze at a distant object

Use peripheral vision while looking straight ahead

Without moving your eyes, look up and down. Connect side spaces to your vision.

Focus on everything as your eyes soften.

Keep breathing

Stay as long as you like

11. Be intimate

We kiss, moan, and breathe deeper during love. We get dopamine, oxytocin, serotonin, and vagus nerve stimulation.

Why not?

To sum up

Here are 11 vagus nerve resets:

1. Stretch

2. Breathe

3. Hum/Chant

4. More humor

5. Amuse yourself

6. Spend time outdoors

7. Leap into chilly water

8. Exercise

9. Play music with brainwaves.

10. Make gentle eyes.

11. Be intimate

If these words have inspired you, try my favorite breathwork technique. Combining breathing, chanting, and brainwave music. Win-win-win :)

https://tomconnor.me/wp-content/uploads/2021/08/10x-Engineer-Mental-Models.pdf

I keep returning to the same mental models and tricks after writing and reading about a wide range of topics.

Top 12 mental models

12.

Survival bias - We perceive the surviving population as remarkable, yet they may have gotten there through sheer grit.

Survivorship bias affects us in many situations. Our retirement fund; the unicorn business; the winning team. We often study and imitate the last one standing. This can lead to genuine insights and performance improvements, but it can also lead us astray because the leader may just be lucky.

11.

The Helsinki Bus Theory - How to persevere Buss up!

Always display new work, and always be compared to others. Why? Easy. Keep riding. Stay on the fucking bus.

10.

Until it sticks… Turning up every day… — Artists teach engineers plenty. Quality work over a career comes from showing up every day and starting.

9.

WRAP decision making process (Heath Brothers)

Decision-making WRAP Model:

W — Widen your Options

R — Reality test your assumptions

A — Attain Distance

P — Prepare to be wrong or Right

8.

Systems for knowledge worker excellence - Todd Henry and Cal Newport write about techniques knowledge workers can employ to build a creative rhythm and do better work.

Todd Henry's FRESH framework:

1. Focus: Keep the start in mind as you wrap up.

2. Relationships: close a loop that's open.

3. Pruning is an energy.

4. Set aside time to be inspired by stimuli.

5. Hours: Spend time thinking.

7.

Black Box Thinking…..

BBT is learning from mistakes. Science has transformed the world because it constantly updates its theories in light of failures. Complexity guarantees failure. Do we learn or self-justify?

6.

The OODA Loop - Competitive advantage

O: Observe: collect the data. Figure out exactly where you are, what’s happening.

O: Orient: analyze/synthesize the data to form an accurate picture.

D: Decide: select an action from possible options

A: Action: execute the action, and return to step (1)

Boyd's approach indicates that speed and agility are about information processing, not physical reactions. They form feedback loops. More OODA loops improve speed.

5.

Know your Domain 

Leaders who try to impose order in a complex situation fail; those who set the stage, step back, and allow patterns to develop win.

https://vimeo.com/640941172?embedded=true&source=vimeo_logo&owner=11999906

4.

The Three Critical Gaps

• Information Gap - The discrepancy between what we know and what we would like to know

• Gap in Alignment - What individuals actually do as opposed to what we wish them to do

• Effects Gap - the discrepancy between our expectations and the results of our actions

3.

Theory of Constraints — The Goal  - To maximize system production, maximize bottleneck throughput.

• Goldratt creates a five-step procedure:

1. Determine the restriction

2. Improve the restriction.

3. Everything else should be based on the limitation.

4. Increase the restriction

5. Go back to step 1 Avoid letting inertia become a limitation.

Any non-constraint improvement is an illusion.

2.

Serendipity and the Adjacent Possible - Why do several amazing ideas emerge at once? How can you foster serendipity in your work?

You need specialized abilities to reach to the edge of possibilities, where you can pursue exciting tasks that will change the world. Few people do it since it takes a lot of hard work. You'll stand out if you do.

Most people simply lack the comfort with discomfort required to tackle really hard things. At some point, in other words, there’s no way getting around the necessity to clear your calendar, shut down your phone, and spend several hard days trying to make sense of the damn proof.

1.

Boundaries of failure - Rasmussen's accident model.

Rasmussen modeled this. It has economic, workload, and performance boundaries.

The economic boundary is a company's profit zone. If the lights are on, you're within the economic boundaries, but there's pressure to cut costs and do more.

Performance limit reflects system capacity. Taking shortcuts is a human desire to minimize work. This is often necessary to survive because there's always more labor.

Both push operating points toward acceptable performance. Personal or process safety, or equipment performance.

If you exceed acceptable performance, you'll push back, typically forcefully.

Consider yourself lucky if your last FAANG interview was rejected.

FAANG—Facebook, Apple, Amazon, Netflix, Google

(I know its manga now, but watch me not care)

These big companies offer many benefits.

1. large salaries and benefits

2. Prestige

3. high expectations for both you and your coworkers.

However, these jobs may have major drawbacks that only become apparent when you're thrown to the wolves, so it's up to you whether you see them as drawbacks or opportunities.

I know most college graduates start working at big tech companies because of their perceived coolness.

I've worked in these companies for years and can tell you what to expect if you get a job here.

Little fish in a vast ocean

The most obvious. Most billion/trillion-dollar companies employ thousands.

You may work on a small, unnoticed product part.

Directors and higher will sometimes make you redo projects they didn't communicate well without respecting your time, talent, or will to work on trivial stuff that doesn't move company needles.

Peers will only say, "Someone has to take out the trash," even though you know company resources are being wasted.

The power imbalance is frustrating.

What you can do about it

Know your WHY. Consider long-term priorities. Though riskier, I stayed in customer-facing teams because I loved building user-facing products.

This increased my impact. However, if you enjoy helping coworkers build products, you may be better suited for an internal team.

I told the Directors and Vice Presidents that their actions could waste Engineering time, even though it was unpopular. Some were receptive, some not.

I kept having tough conversations because they were good for me and the company.

However, some of my coworkers praised my candor but said they'd rather follow the boss.

An outdated piece of technology can take years to update.

Apple introduced Swift for iOS development in 2014. Most large tech companies adopted the new language after five years.

This is frustrating if you want to learn new skills and increase your market value.

Knowing that my lack of Swift practice could hurt me if I changed jobs made writing verbose Objective C painful.

What you can do about it

1. Work on the new technology in side projects; one engineer rewrote the Lyft app in Swift over the course of a weekend and promoted its adoption throughout the entire organization.

2. To integrate new technologies and determine how to combine legacy and modern code, suggest minor changes to the existing codebase.

Most managers spend their entire day in consecutive meetings.

After their last meeting, the last thing they want is another meeting to discuss your career goals.

Sometimes a manager has 15-20 reports, making it hard to communicate your impact.

Misunderstandings and stress can result.

Especially when the manager should focus on selfish parts of the team. Success won't concern them.

What you can do about it

1. Tell your manager that you are a self-starter and that you will pro-actively update them on your progress, especially if they aren't present at the meetings you regularly attend.

2. Keep being proactive and look for mentorship elsewhere if you believe your boss doesn't have enough time to work on your career goals.

3. Alternately, look for a team where the manager has more authority to assist you in making career decisions.

After a certain point, company loyalty can become quite harmful.

Because big tech companies create brand loyalty, too many colleagues stayed in unhealthy environments.

When you work for a well-known company and strangers compliment you, it's fun to tell your friends.

Work defines you. This can make you stay too long even though your career isn't progressing and you're unhappy.

Google may become your surname.

Workplaces are not families.

If you're unhappy, don't stay just because they gave you the paycheck to buy your first home and make you feel like you owe your life to them.

Many employees stayed too long. Though depressed and suicidal.

What you can do about it

1. Your life is not worth a company.

2. Do you want your job title and workplace to be listed on your gravestone? If not, leave if conditions deteriorate.

3. Recognize that change can be challenging. It's difficult to leave a job you've held for a number of years.

4. Ask those who have experienced this change how they handled it.

You still have a bright future if you were rejected from FAANG interviews.

Rejections only lead to amazing opportunities. If you're young and childless, work for a startup.

Companies may pay more than FAANGs. Do your research.

Ask recruiters and hiring managers tough questions about how the company and teams prioritize respectful working hours and boundaries for workers.

I know many 15-year-olds who have a lifelong dream of working at Google, and it saddens me that they're chasing a name on their resume instead of excellence.

This article is not meant to discourage you from working at these companies, but to share my experience about what HR/managers will never mention in interviews.

Read both sides before signing the big offer letter.

After a decade in large tech, I know how software engineers were interviewed. I've seen outstanding engineers fail interviews because their responses were too vague.

So I wrote Nail A Coding Interview: Six-Step Mental Framework. Give candidates a mental framework for coding questions; help organizations better prepare candidates so they can calibrate traits.

Recently, I sold more than 100 books, something I never expected.

In this essay, I'll describe my publication journey, which included self-doubt and little triumphs. I hope this helps if you want to publish.

It was originally a Medium post.

How did I know to develop a coding interview book? Years ago, I posted on Medium.

Six steps to ace a coding interview Inhale. blog.devgenius.io

This story got a lot of attention and still gets a lot of daily traffic. It indicates this domain's value.

Converted the Medium article into an ebook

The Medium post contains strong bullet points, but it is missing the “flesh”. How to use these strategies in coding interviews, for example. I filled in the blanks and made a book.

I made the book cover for free. It's tidy.

Shared the article with my close friends on my social network WeChat.

I shared the book on Wechat's Friend Circle (朋友圈) after publishing it on Gumroad. Many friends enjoyed my post. It definitely triggered endorphins.

In Friend Circle, I presented a 100% off voucher. No one downloaded the book. Endorphins made my heart sink.

Several days later, my Apple Watch received a Gumroad notification. A friend downloaded it. I majored in finance, he subsequently said. My brother-in-law can get it? He downloaded it to cheer me up.

I liked him, but was disappointed that he didn't read it.

The Tipping Point: Reddit's Free Giving

I trusted the book. It's based on years of interviewing. I felt it might help job-hunting college students. If nobody wants it, it can still have value.

I posted the book's link on /r/leetcode. I told them to DM me for a free promo code.

Momentum shifted everything. Gumroad notifications kept coming when I was out with family. Following orders.

As promised, I sent DMs a promo code. Some consumers ordered without asking for a promo code. Some readers finished the book and posted reviews.

My book was finally on track.

A 5-Star Review, plus More

A reader afterwards DMed me and inquired if I had another book on system design interviewing. I said that was a good idea, but I didn't have one. If you write one, I'll be your first reader.

Later, I asked for a book review. Yes, but how? That's when I learned readers' reviews weren't easy. I built up an email pipeline to solicit customer reviews. Since then, I've gained credibility through ratings.

Learnings

I wouldn't have gotten 100 if I gave up when none of my pals downloaded. Here are some lessons.

• Your friends are your allies, but they are not your clients.

• Be present where your clients are

• Request ratings and testimonials

• gain credibility gradually

I did it, so can you. Follow me on Twitter @imgracehuang for my publishing and entrepreneurship adventure.

It's ok and even desired to be unprofitable if you're gaining revenue at a reasonable cost and have 100%+ net dollar retention, meaning you never lose customers and expand them. To estimate the acceptable cost of new SaaS revenue, we compare new revenue to operating loss and payback period. If you pay back the customer acquisition cost in 1.5 years and never lose them (100%+ NDR), you're doing well.

To evaluate payback period, we compared new revenue to net operating loss for the last 73 SaaS companies to IPO since October 2017. (55 out of 73). Here's the data. 1/(new revenue/operating loss) equals payback period. New revenue/operating loss equals cost of new revenue.

Payback averages a year. 55 SaaS companies that weren't profitable at IPO got a 1-year payback. Outstanding. If you pay for a customer in a year and never lose them (100%+ NDR), you're establishing a valuable business. The average was 1.3 years, which is within the 1.5-year range.

New revenue costs $0.96 on average. These SaaS companies lost $0.96 every $1 of new revenue last year. Again, impressive. Average new revenue per operating loss was $1.59.

Loss-in-operations definition. Operating loss revenue COGS S&M R&D G&A (technical point: be sure to use the absolute value of operating loss). It's wrong to only consider S&M costs and ignore other business costs. Operating loss and new revenue are measured over one year to eliminate seasonality.

Operating losses are desirable if you never lose a customer and have a quick payback period, especially when SaaS enterprises are valued on ARR. The payback period should be under 1.5 years, the cost of new income < $1, and net dollar retention 100%.