A neuroscientist shares the 3 exercises she does to stop stress and anxiety—in 'just a few minutes'

During stressful situations, our brain can feel like our worst enemy, causing us to shut down with anxious thoughts or heart palpitations.

Intense anxiety activates the sympathetic nervous system, a network of nerves that trigger the "fight or flight" response to perceived danger. But instead of protecting us, it is sometimes inconvenient — for example, if you're at a job interview and trying to impress a potential future employer.

Luckily, you have more power over this than you might think. As a neuroscientist, I use three exercises that take just a few minutes to reset my nervous system and feel calm again:

1. The mindful sigh

You should be sitting comfortably for this. I do it at my desk when I notice key symptoms of stress like shallow breathing, tense shoulders or an increased heart rate.

1. Take a deep, long inhale through your nose for five seconds and hold.
2. Take another quick inhale for one second and hold for three seconds. 
3. Sigh a slow, long exhale through your mouth for six seconds. 
4. Repeat the cycle three times.  

That quick second inhale causes the air sacs in the lung, which collapses when we're done inhaling, to reinflate with air. As a result, the surface area in the lungs increases, and releases carbon dioxide from the body more efficiently. This helps to relax the body.

Long exhales cause a slight increase in pressure to the receptors in the heart, signaling the brain to slow down the heart rate.

2. The half-salamander  

This is called the half-salamander because your eyes are moving while your head is kept still, similar to a salamander's behavior.

1. Sit or stand in a comfortable position, with your head facing forward.
2. Shift your eyes to the right without turning your head.
3. Tilt your head towards your right shoulder and hold for 30 to 60 seconds.
4. Let your head come back up to its neutral position and shift your eyes to look forward again.
5. Repeat the same steps on the other side.

The half-salamander stimulates the vagus nerves — a system that controls your heart rate — and triggers a relaxation response in our body.

3. The full salamander  

This one is harder to do if you are at your desk or in the office, so it's a great longer-term exercise to try at home.

1. Kneel on all fours, with your head facing down.
2. Look to the left without turning your head.
3. Tilt your head to the left.
4. Let your left spine twist with the head tilted to the left.
5. Hold for 30 to 60 seconds 
6. Bring your head and spine to the center to straighten out.
7. Repeat the same steps on the other side.

While anxiety can be scary, understanding how our bodies and brains react during those moments can remove some of the pressure and help us take control of our nervous system.

Dr. Tara Swart Bieber is a neuroscientist, medical doctor and senior lecturer at MIT Sloan. She is the author of "The Source: The Secrets of the Universe, the Science of the Brain," and hosts the podcast Reinvent Yourself with Dr. Tara. Follow her on Twitter and Instagram.

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