If you cheer on a group of exhausted marathon runners, you may wonder why they look happy. There is a phenomenon called the "runner's high" which floods the brain and body with feel good chemicals.

Chances are a runner will say something about the fabled runner's high if you ask them. A runner's high is something to think about. What does it do to the body? Is it possible that it will make you feel drunk?

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You can finish a run with a smile on your face, even though it takes a lot of work. The runner's high is the strange euphoria that comes after a long run.

According to a report by the Chicago Tribune, the term "runner's high" probably started in the 1970s during the first recreational running boom in the US.

David Raichlen, an evolutionary biologist at the University of Southern California, told Live Science that it's used as a shorthand for a range of changes to your Physiological State that occur with Exercise.

subjective things like improved mood and a general sense of wellbeing are included in the range of changes. Over the past few decades, one particular group of exercise-related chemicals has received a lot of scientific attention.

In the 2001 film "Legally Blonde," the character Elle Woods remarked that exercise gave her a sense of well-being. You are happy because of endorphins. People who are happy don't shoot their spouses.

Your body releases a cocktail of chemicals when you exercise. The effects of these compounds are similar to those of Opioids. A review paper published in the Hawaii Medical Journal shows that they help to relax your body and decrease your perception of pain. People still feel great after a long run even though they experience some pain.

During aerobic exercise, your body begins to release a cocktail of chemicals, including several different endorphins.

Exercise also releases the "feel-good" chemical dopamine, a heavy-hitter for your body's reward system. (Image credit: Apirakthanakorn/Shutterstock)
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For a long time, scientists believed that a tired runner's mood was boosted by the effects of the pain-relief drug endorphins. Endorphins don't cross the blood-brain barrier so they shouldn't be linked to happiness.

Scientists found a lot of endocannabinoids and neurotransmitters that hadn't previously been associated with exercise percolating in various tissues when they took a closer look at the chemicals in runners' bodies. The endocannabinoids can affect moods. The chemicals can cross the blood brain barrier.

How does a runner's high affect the body and mind?

According to a review published in the journal Psychoneuroendocrinology, endocannabinoids are the key to peace. The research in the journal Acta pharmacologica sinica shows that endocannabinoids are related to the active ingredient in cannabis.

Anandamide is one of the endocannabinoids that can cross the blood brain barrier. endocannabinoids are produced naturally within the body and tend to have more subtle effects on our mental state. Raichlen explained that a runner's high is less of a high and more of a gentle lift.

Dopamine, a heavy-hitter for the body's reward system, is related to motivation and why some people are more motivated than others. This pleasure inducing neurotransmitter is released when you win the lottery, or have sex. According to research published in the journal Frontiers in Psychology, dopamine might contribute to the feeling of a runner's high.

Achieving a runner's high

Long-distance running is one of the most obvious ways to get a runner's high. It may take several miles for the effects to kick in, though it's difficult to quantify precisely when, where and for how long a runner's high will occur.

Not every runner will be able to get a runner's high, according to a professor of neuroscience at a university.

The term "runner's high" indicates that you can only experience these changes while pounding the pavement, but other aerobic activities, including biking, swimming and strenuous hiking, can also cause the same response.

Humans are not the only animals that have shown signs of being high. Experiments have shown a similar phenomenon in animals. According to research published in the Journal of Experimental Biology, Raichlen's lab has tested dogs and ferrets by putting them on a treadmill and looking for the effects of exercise. Blood tests showed elevated levels of endocannabinoids in the dogs' systems after 30 minutes of running

Raichlen said that they did not see that in the ferrets.

Is a runner's high good for you?

It makes exercising more enjoyable if you achieve a runner's high. According to the American Heart Association, exercising is a key component of long-term heart health. According to research published in the Primary Care Companion to The Journal of Clinical Psychiatry, exercise can have significant mental health benefits such as reducing anxiety and stress.

There is no proof that a runner's high is healthy. Raichlen said at the very least that it's not bad. Do you want to lace up your shoes? As long as it takes you, you're free to chase that runner.