What Actually Happens?

Engaging in endurance training triggers numerous psychophysical effects, such as stress relief, mood enhancement, and diminished pain sensitivity. For some individuals, these benefits might represent a form of "runner's high," making the experience quite personal.

Nevertheless, there is also a more tangible, drug-like response associated with running. This is where confusion often arises. Research from the 1980s suggested that prolonged running led to an extended release of endorphins, which would attach to the same opioid receptors as substances like morphine and heroin, thus creating a similar euphoric effect. However, this theory is flawed.

The challenge with endorphins lies in their inability to cross the blood-brain barrier due to their large molecular structure, which prevents them from impacting brain function. In essence, runner's high arises from endocannabinoids stimulating the brain's reward system.

This euphoric feeling is closely linked to elevated levels of endocannabinoids in the bloodstream. Unlike endorphins, these compounds can penetrate the blood-brain barrier and interact with the brain. Endocannabinoids activate the same receptors that various psychoactive substances do (including marijuana), providing pain relief and a calming effect, similar to a natural opioid but much safer than pharmaceutical alternatives.

Robust research supports this mechanism. For instance, one study showed that participants who ran exhibited higher circulating endocannabinoid levels, reduced anxiety, and increased pain tolerance. Additional studies involving both humans and dogs noted elevated blood endocannabinoid levels in running subjects compared to control groups.

Achieving the Runner’s High

Interestingly, the release of endocannabinoids is highly dependent on the intensity of exercise. A study involving different treadmill settings revealed that both very high and very low running intensities did not lead to significant increases in endocannabinoid levels post-exercise. Conversely, moderate aerobic activity resulted in much higher levels of these neurotransmitters.

“This could explain why long-distance runners, who typically maintain a moderate and steady pace, are more likely to report experiencing the runner’s high compared to high-intensity sprinters.” — Lily Yang

In Conclusion

Ultimately, experiencing an exercise-induced "high" occurs when you engage in activities you love. Do you need to trigger endocannabinoid release to enjoy the post-run feel-good factor? Probably not. Endurance running inherently boosts confidence, alleviates stress, and promotes overall well-being. Run for the multitude of mental and physical benefits it offers, and if you're fortunate, you might also experience that euphoric high along the way.

“There are moments in time when running allows you to see how wonderful your life is.” — Kara Goucher, Olympian

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The first video explores how to consistently achieve a euphoric state during running, offering practical tips and insights.

The second video delves into the concept of runner's high, explaining its underlying mechanisms and how it can be experienced.