Sparking Up a Runner's High

Pixabay

The body aches felt total, all-encompassing and pervasive. Over the course of a sweltering day at Gibson Ranch County Park, I’d ran eight miles and hurdled 24 obstacles while participating in the Tough Mudder Classic. The finish line was within sight, but I was tired and tangled in the course’s final obstacle, a 25-foot-tall, A-frame-shaped behemoth called the Mudderhorn.

Dry mud caked my clothes and skin, my arms and legs felt floppy like noodles and I still shook from the Electroshock Therapy obstacle. Jittery, I hitched my arms in the cargo net as I struggled over the Mudderhorn’s peak, trying my best to avoid glancing at the ground below. Heights were never my thing. 

This was back in June of 2019, a period right at the start of my ongoing fitness journey. Running wasn’t yet a part of my regular schedule and my first attempts at indoor bouldering were still months away. Though I’m still green, I was even greener back then. 

The Tough Mudder was my first foray into racing and obstacle events. It was a taxing task, and as I crossed the finish line, a wave of relief washed over me. After collecting my finisher headband and shirt, I hobbled to my car and drove back to my apartment. 

Euphoria crept up on me during the ride home, a pleasurable sensation that pulsed outwards from my core. At first, it manifested as an immense sense of satisfaction, but slowly, it morphed into a general feeling of levity, both of the mind and body. Physical aches were pushed to the periphery of my awareness and my mind buzzed with good vibes. 

With the pain a dull phantom of what it once was, I felt ready to take on the world. A beautiful glow hugged the rest of the day.

When I look back on the experience, I believe this was my first encounter with the phenomenon known as “runner’s high.” I experienced this ephemeral state again during and after my first half marathon the following October. More recently, I was reacquainted with it following my first 50K last month.    

But what’s going on in the body of a person experiencing runner’s high? 

For a long time, I was under the impression that the blissful sensation was attributable solely to endorphins, endogenous chemicals that target our body’s opioid receptors. While working on a short listicle about exercise for the UC Davis College of Biological Sciences, I learned the science behind runner’s high is more nuanced. 

According to Dr. Keith Baar, a professor of molecular exercise physiology at UC Davis, endurance exercise stimulates the body’s production of endocannabinoids. These neurotransmitters act on our cannabinoid receptors, which are the same receptors targeted by cannabinoids (THC, CBD) present in marijuana.

Science has revealed that endocannabinoids are much more involved in runner’s high than endorphins. Researchers studying runner’s high have noted endorphins can’t pass between the blood-brain barrier. Endocannabinoids can.  

In a study published in the Proceedings of the National Academy of Sciences, German researchers found that “a lipid-soluble endocannabinoid called anandamide—also found at high levels in people’s blood after running—can travel from the blood into the brain, where it can trigger a high,” reported to Scientific American. “The team’s findings suggest that endocannabinoids such as anandamide help cause runner’s high.”    

With such a reward system built into our biology, it’s hard not to believe we’re neurochemically wired to run. 

As Baar noted during our interview, “The animals that have the most stimulation of endocannabinoids are the ones that exercise the most out of enjoyment.” 

And we are, after all, animals. 

So what are you waiting for? Get out there and spark up a runner’s high. 

Happy running!