Runner's High, Endorphins and Questions

Runner’s High, Endorphins and Doubts

A week ago, in the March 27th issue of the New York Times, there was an article that caught my eye. The title was “Yes, Running Can Make You High” written by Gina Kolata. The newspaper article discussed the mysterious euphoric feeling that long distance runners experienced after rigorous sessions of cardio training (4). Being a die-hard runner and soccer player myself, my interests resulted to me reading the rest of the article. Afterwards, I started to question my own experiences of this so-called “Runner’s High”. The article discussed different variations of post-workout symptoms. These symptoms vary drastically, like a spectrum from feeling light, lean and energetic to feeling noxious and sick. I have experienced both extremes.

Runner’s High has always been a hypothesis that was proposed to the scientific world, however was never able to accumulate enough evidence to prove its definite existence. However, recent studies have been able to compile scientific evidence to not only prove its existence, but also to explain its cause. The ‘Runner’s High’ phenomenon suggests that those who perform rigorous amounts of cardio exercise secrete high levels of endorphins from the brain during the workout. Endorphins are neurotransmitters found in the brain that interact with opiate sensory neurons. These neurotransmitters have pain relieving properties and higher levels present in the human nervous system results that person to be in a happier mood (1). Evidence of Runner’s High was difficult to grasp due to the difficulty in tracking pre/post-workout Endorphin levels in people’s blood. Although the endorphin levels were able to be measured, the cause of secretion was not distinguishable; between actual Runner’s High endorphin levels and the human body’s automatic response of endorphin levels rising as a stress response of oxygen lacking in the brain. But Dr. Henning Boecker of Univeristy of Bonn in Germany have recently submitted a report in the journal ‘Cerebral Cortex’, that presents a significant amount of scientific evidence for this phenomenon and confirms the fact that running actually does release a significant amount of endorphins in the brain and this directly effects mood changes, thus, a sense of euphoria after a workout (7).

The evidence was compiled together by performing PET (Positron Emission Tomography) scans on runners’ brains before and after workouts. PET scans have the capability to show chemicals currently present in the brain (8). Regardless of the runners’ moods, the investigation was targeted specifically on endorphin levels, comparing the specific areas and endorphin levels of the brain before and after a rigorous two-hour run. The conclusion reached stated that endorphins were produced during the running process and that they were directly migrating to the limbic and prefrontal areas of the brain. The limbic lobe of the brain controls the olfactory senses and emotions and the prefrontal lobe effects the expression of personality and social behavior (2,3). Both areas are highly related to controlling human emotions and their mood swings.

There is also linkage of this phenomenon with respect to the study of pain perception. Dr. Boecker believes that there is enhancement of pain tolerance for those who are running versus those who are not running. For examples, there have been incidents where people have had such drastic changes in pain tolerance that despite the presence of a stress fractures or even a heart attack, those who are running do not sense the pain of it occurring. Dr. Boecker claims that this is due to the increased level of endorphins that are secreted during the exercise process. Like morphine or other pain killing drugs, endorphins interact with opiate sensory neurons in the brain, thus, higher levels can cause the brain to not feel pain and only euphoria. Dr. Boecker is continuing his current research with recruitment of twenty marathon runners along with non-athletes to study pre/post-workout pain perception along with other PET scans of the brain. The addition of non-athletes gives perspective of endorphin levels according to the intensity of the exercise and for those who do not exercise on a normal day basis.

From my own experience, I can relate to the results of the research on Runner’s High. Especially during soccer games, I cannot feel pain when kicked or tackled, however when the game is over, I cannot walk due to excruciating pain and exhaustion. While I am running a 5K, I feel light, nimble and alert. However, my end symptoms can vary from feeling euphoria or from feeling noxious and exhausted. Usually it is times when I have not worked out for a long period of time that I feel the painful feel post-workout, however after getting into the routine, the feeling of happiness and pleasure increases. Maybe Runner’s High is a symptom that can only be felt after a certain threshold of energy expenditure is reached. Until that threshold is reached, the body is only feeling exhaustion after the workout. The high pain tolerance can be due to the sympathetic nervous system kicking in, where the body is alert and heart rate and blood pressure are accelerated and increased. Due to the body’s focus on being alert, the nervous system is not concentrated on the hurt areas of the human body, which is probably why after the workout, when the parasympathetic nervous system restores itself, pain is felt along with exhaustion and even hunger. Although the evidence of Runner’s High is highly probable and believable even for my own personal experiences, I feel that there are also other aspects that contribute into the euphoric feeling, such as threshold levels and personal fitness. Also, I question the role of different parts of the nervous system when Runner’s High is linked with pain tolerance, especially with the presence of a parasympathetic and sympathetic nervous system response (5,6). Many gray areas are still yet to be confirmed.

*Cited Sources

1. http://www.encyclopedia.com/doc/1E1-endorphi.html

2. http://www.brainexplorer.org/glossary/prefrontal_cortex.shtml

3. http://biology.about.com/library/organs/brain/bllimbic.htm

4. http://www.nytimes.com/2008/03/27/health/nutrition/27best.html

5. http://www.medterms.com/script/main/art.asp?articlekey=4770

6. http://home.swipnet.se/sympatiska/nervous.htm

7. http://cercor.oxfordjournals.org/cgi/content/abstract/bhn013v1?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=Runner%27s+High&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT

8. http://www.webmd.com/a-to-z-guides/positron-emission-tomography