Welcome to Stretch, your guide to experimenting with your mental, emotional, and physical performance. Guaranteed to teach you something new about your mind and body.

⏪ Last edition, we spoke about quick, easy and naturalenergy boosters for when you’re on the road or short on time. Catch up on that here.

⏩ Today, we’re talking about how running gives you calm, persistence and energy, making you feel like anything’s possible. But why is that, from a brain and body perspective?

Run for calm, persistence and energy

I’m training for my first marathon in November—in Firenze, Italy!

I signed up for a marathon a few years ago but had to throw in the towel because of persisting shins pain. But I want to try again, for a very simple reason:

So I want to make running a cornerstone habit—not just when I can squeeze in the time. A strict marathon training plan forces me to structure my mornings and evenings around my runs. I allow myself a little bit of flex to move things around, the only rule is I can’t break the chain of the red crosses more than once. (Inspired by Seinfeld’s Don’t break the chain strategy.)

But the question I want to dig into is: why does running have such an incredible effect on me, like anything’s possible?

It always feels like magic but more than anything, it’s physiological and neurochemical. (Doesn’t make it any less magical, of course!). Here’s why:

1. The more I run, the less I worry

Ever noticed how most problems seem more manageable after a run outside?

There is a neurological reason for that.

When you move forward, you create “self-generated optic flow.” These are the visual images passing by on all sides of your visual field as you move. Your eyes move to engage with this optic flow, and this has a powerful effect on the nervous system.

It reduces the amount of activity in an area of the brain called the amygdala—which plays a key role in feelings of anxiety and threat detection. This is calming and reduces levels of stress, overwhelm and overthinking. You stop worrying about the presentation you need to finish, or all the things that could go wrong on that project.

Optic flow is the opposite of sitting still, staring at a screen, which is what most of us tend to do when we’re thinking through a problem.

There’s just one caveat:

The movement has to be 'self-generated'. Treadmills or Peloton don’t count, unfortunately, as you don’t get that optic flow.

I’ll admit, the first 10-15 minutes of a run don’t typically feel relaxing or calming. It always takes a bit of time to get into it, but once I get over that period of agitation, I hit my stride. (Pushing through the initial agitation doesn’t just apply to exercise but also to deep work and focus!) I always come back home feeling lighter and calmer.

2. The more I run, the more I get done

In her book The Joy of Movement, psychologist Kelly Mcgonigal shares this finding from research with runners:

Endocannabinoids are brain chemicals that tend to decrease pain, improve mood, and set off positive neurotransmitters like dopamine and endorphins.

This is what creates the famous runner's high feeling.

Except it's not really a runner's high.

It's a persistence high.

The research shows that the high isn’t about the physical act of running in and of itself. It’s about the continuous moderate intensity—requiring some level of persistence.

That means that all you need to do is do something that’s moderately difficult for you and stick with it for at least twenty minutes.

That’s so important to keep in mind. Going for a run doesn’t mean you need to carve out an hour. Just a quick 20 minutes run where I get my heart rate up and my body sweating, and I notice how that persistence high bleeds into the rest of my day. Annoying tasks feel just that little bit easier. There’s less internal resistance and negotiation. I move more quickly and am less distracted.

There’s this Zen proverb that says “If you don’t have time to meditate for an hour everyday, you should meditate for two hours.” For me, it’s the same with running. The days where I’m tempted to skip my run because “I don’t have the time”, are the days I especially need to go out.

3. The more I run, the more energy I have

We’ve become so disconnected from nature that we forget that natural light is incredibly important for our energy levels and sleep quality.

Natural light is our nervous system's primary “timekeeper”—the way in which the body knows what time of day it is and when to turn certain functions on and off; when to be alert and when to be sleepy.

In the retina (the light-sensitive inside lining of the eye), there’s a specialized group of neurons. When these neurons are triggered by light, they send electrical signals to the circadian clock in our brain, setting in motion a cascade of hormone releases in our body—like dopamine and cortisol for alertness during the day, and melatonin for sleepiness in the evening.

These neurons respond best to the quality and intensity of natural light when the sun is low in the sky—like in the early morning or evening.

So going outside for a run around those times is the perfect way to get the benefits from natural light. (It’s okay if it’s cloudy—there’s still more than enough light energy coming through the clouds.)

What else I’m up to…