What Happens in Our Brain and Body When We Run

I once ran a relay race with friends that required us to collectively run 200 miles over a weekend in New Hampshire. I found myself getting ready to run four miles at 3 AM (my second leg with one more to go later in the day). I never ran in the dark before and I certainly never ran at 3 AM. I had my headlamp and reflection vest on. My team members, fatigued but filled with adrenaline, cheered me on just as I cheered them when it was their turn to run. I was off, initially with other runners but eventually on my own, at my own steady pace. I suddenly stopped feeling tired. My senses were heightened, with very few sounds other than my feet hitting the pavement, runners and cars in the distance, and the wind wooshing through the trees. The stars were bright and big on this clear night. The moon was full and lit up my path, to the point that I did not even need my headlamp. I was so grateful and at peace. Euphoria washed over me and it made me want to kiss the ground I was running on. It was just so beautiful, to experience the earth at an hour when I would typically be asleep. To see the moon light my way and be my guide. To be with friends who were all working on the same goal no matter how tired. I thought to myself, “So this must be the runner’s high everyone talks about.” I had no idea that a few years later I’d own a private practice with the intention of helping clients experience this joy. I began doing research and the information I discovered was not only validating for me personally, but it has inspired me to spread the information as much as I can. This growing body of research indicates that running improves our mental health…but how?

I’m going to simplify what I’ve come across in studies and books on this subject. In order to understand how running impacts mental health, we must understand what is happening in the brain. Let’s start with what most people are familiar with and what I described earlier, the “runner’s high.” The runner’s high is generally described as a feeling of euphoria that occurs during a run. We usually hear about endorphins and how great it is to get those endorphins going when we exercise. Recent research has challenged the idea that it is endorphins actually creating the euphoria and changes in mood. Although endorphins play a role in blocking pain when we run, they are not able to have an impact on our mood because they don’t actually enter the bloodstream and change the chemistry in our brain. We have recently learned that there is also a different system involved when it comes to this euphoria, which you may have not heard of: the endocannibinoid system. Running or exercising at a moderate intensity releases endocannibinoids, which impacts the body much like how the cannabis plant does. Endocannibinoids naturally occur within the body and can help us enter a meditative, calm, and euphoric state. We may also experience disappearance of worries, alleviated pain, heightened senses, slowing of time, empowerment, and greater connection to others. Endocannibinoids have been referred to as the “don’t worry, be happy” chemicals that have been biologically built in to our bodies. These chemicals not only help us in the moment, but can remain in our system and ward off depression and anxiety symptoms. Running can also help mitigate stress that builds up in our bodies by cueing our parasympathetic nervous system, which in turn regulates our feelings of safety and helps us to feel calm.

Understanding the biology that is in play when we run or move could help us to better undertand why it happens in the first place. Researchers have theorized that the endocannibinoid system is likely activated during moderate exercise for evolutionary reasons. A calm state, reduction in pain, connection to others, and feelings of bliss could all serve as the reward for a behavior that was required for survival when we were largely foragers and hunters. If we are rewarded for physical exertion, we are more likely to do it, repeat it, and more likely to survive.

Dr. Kelly McGonigal coins the term “persistance high” in her book, The Joy of Movement when she writes, “Anything that keeps you moving and increases your heart rate is enough to trigger nature’s reward for not giving up. There’s no objective measure of performance you must achieve, no pace or distance you need to reach, that determines whether you experience an exercise-induced euphoria. You just have to do something that is moderately difficult for you and stick with it for at least twenty minutes. That’s because the runner’s high isn’t a running high. It’s a persistance high.”

Studies also indicate that it is not just running that can activate the endocannibinoid system. Cycling, hiking outside, dancing, swimming, and walking at an incline can have the same impact and are all activities that would get the heart rate up. The more we move, the more the brain builds capacity for endocannibinoid binding sites. In other words, we can experience the runner’s high even more if we are consistent in our movement. It may be difficult for some to achieve this if they are new to moderate exercise and unable to sustain movement for at least twenty minutes, but it may be a goal worth working toward! Our bodies are built to experience perseverance and the benefits of perserverance have a major impact on our mental health.

I know that the more that I have moments like I did in my race, the more peaceful and mindful I am as a person. I will warn you, not all runs can feel like that and it is important to not worry or stress if you are not achieving this feeling. We can also greatly benefit from runs that have no agenda or goal, allowing us to stay in the present moment. You get to determine how you want each walk or run to be, maybe with a certain goal in mind or maybe to simply just be with yourself. I believe that we can all access joy from movement if we are taught the tools to get there and are willing to work on it…much like most obstacles in life.