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The Body's Natural Painkillers

Stacy Blecher's picture

When I had my wisdom teeth removed my doctor told me to go home, rest and take a pill called codeine if I experienced any great pain.  I gladly followed his orders.  Had my doctor told me to go immediately to the gym and run on the treadmill until I felt better I would have looked at him like he was crazy and I doubt that I would have obeyed his commands.  While the two treatments for pain –codeine and exercise –seem to be opposites, recent neurobiological research suggests that a doctor would not be unjustified prescribing a hearty dose of physical activity to a patient suffering from pain.

When the body is subjected to a stress, such as a continuous workout at a level on intensity between moderate and high, a peptide is produced in the pituitary gland and hypothalamus is released into the central nervous system (1).  This peptide is an endogenous opiod biochemical compound, better known as an endorphin.  Notice that the scientific name of this compound has the root opioid, meaning that it belongs to the group of chemicals known to most people as opiates.  The use of opiates is stigmatized in our society because drugs such as heroin, methadone and morphine, which are highly addictive, are part of the opioid family.  Yet, the endorphins that are naturally produced in our bodies are of a very similar structure, and therefore have a similar function as the aforementioned drugs.  Swallowing a pill of codeine or injecting a hit of heroin fills the same opioid receptors in the brain that could be filled by participating in a rigorous workout.  These opioid receptors are most commonly found in the part of the brain responsible for integration and perception of pain and emotions.  Knowing the location of these receptors is useful in understanding the effects that opiates have on humans.  It also explains why some refer to endorphins as the body’s natural pain relievers.  While this information has shed light on some inquiries, it has also raises whole new set of questions:

If morphine and endorphins both act as painkillers, why not prescribe exercise?

            In the case of my sore mouth following the removal of my wisdom teeth, the answer to this question is fairly obvious.  While running would release the endorphins needed to soothe the pain, the act of running would also put my mouth at risk of being injured further.  This line of reasoning follows for any condition in which the risk of doing more injury outweighs the ameliorating effects of endorphin release.  However, a strict exercise regimen might be a better treatment for such conditions as chronic pain or depression.  Indeed, some of the leading medical research facilities such as the Mayo Clinic have begun to prescribe physical activity to patients battling chronic pain (3).  In 2007, the Mayo Clinic published research on the effectiveness treating symptoms of depression and anxiety with physical exercise.  Their findings suggest that 30 minutes of exercise a day for at least three to five days a week can significantly improve symptoms of depression (4).  While these findings are extremely recent, in 2001 the American Geriatric Society studied the effect of physical activity on osteoarthritis.  They concluded that moderate-level exercise does not exacerbate osteoarthritis pain nor accelerate the pathological process of osteoarthritis.  In fact, the study strongly suggested that increasing a patient’s level of activity would reduce pain and morbidity (5).  It seems that prescription of daily exercise is a promising alternative to highly addictive drugs currently used by many physicians.

  Why is it that so many people become addicted to heroin and painkilling medication, yet rarely develop an addiction to exercise?

            When physicians prescribe painkillers such as OxyContin, Vicodin and Percocet (all opiates) to alleviate pain, the patient often develops an addiction to the medication.  The same is true when people use opiates recreationally.  The mechanism of addiction is not completely understood by sceintists.  It is thought that upon experiencing the opiate, the brain becomes altered in such a way that causes an influx of extracellular dopamine in the nucleus accumbens, the part of the brain involved in reward and pleasure (6) (7).  Activity in this part of the brain may serves to explain the “high” euphoric feeling that accompanies ingestion of drugs, and that keeps users coming back for more.  While research has shown that levels of dopamine and serotonin increase in the blood during exercise (8), there seem to be far fewer cases of exercise addiction than heroin addiction.  Also, while many enjoy a good workout, few experience a “high”. 

            There are some people who claim to experience what is referred to as a “runner’s high”.  Accounts from people describing a runner’s high include the feelings of euphoria, a trance-like state, and the magical feeling of an out of body experience (9).  On some level, the experience sounds similar to a high one might encounter from taking drugs.  The people claiming to experience “highs” are typically those who consistently run long distances.  Perhaps the chemical changes that take place in the brain during light to moderate bouts of exercise are not drastic enough to produce the “high” sensation.  Heroin is able to quickly penetrate the brain, providing a quick, intense and effortless rush of pleasure which would help to explain why people are more likely to develop a heroin addiction than an exercise addiction. 

            Yet another possible explanation –a less neurologically based explanation –for the fact that more people experience a high from opiate drugs than from exercise, is that the sensation of “high” is socially constructed.  Howard Becker, a sociologist who studied marijuana users in the 1950s, suggested that three important events that needed to happen before a person could use marijuana for pleasure.  The person must learn the proper way to smoke (or otherwise ingest) the drug.  Then, the person must recognize the effects and attribute them to the drug.  Finally, and in this case most importantly, the person must learn to interpret the effects as a pleasurable “high” (10).  It is a socially accepted fact that shooting up heroin gets one high and that popping a couple Vicoden or codeine well make one feel good.  People hear about these experiences all of the time and accept them to be true.  The idea of experiencing a runner’s high is not commonly discussed, in fact, there is a debate about if such a thing even exists.  Perhaps people are going through the proper exercises, feeling the effects of the increased neurochemicals, but failing to recognize the sensations as a pleasurable high.

            The studies of addiction as well as the effects of physical exercise on the brain are both very hot topics in the world of scientific research.  Breakthroughs are being made almost daily in understanding the mechanism of addiction (7)(11).  Scientists and physicians are becoming more aware of the many benefits of tapping into our own natural supply of opiates –endorphins –and prescribing exercise and a healthy diet to patients suffering from chronic pain, depression, and even Alzheimer’s Disease and dementia (12).  Although it is not likely that a doctor will prescribe a 15 mile jog to a patient who has just had wisdom teeth removed anytime soon, perhaps this new information can help scientists find a way to “bottle human endorphins” or synthesize endorphins to create a potentially non-addictive painkiller.   

WWW Sources: 

(1) -, Encyclopedia information about endorphins.

(2) - , Mayo Clinic treats chronic pain with exercise.

(3) - Mayo Clinic treats depression with exercise.

(4) -, Common treatments for Osteoarthritis pain.   

(5) -, Encyclopedia information about the brain.

(6) - , Progress in the Science of Addiction.

(7) -, Brain Chemicals and Modern Life.

(8) -, a runner’s blog.

(9) - Howie’s homepage.

(10) , Brain Injury Halts Smoking…Key to Understanding Addiction.

(11) -, Exercise therapy for the treatment of Alzheimer’s and dementia. Very interesting blog regarding the East / West explanation of the runner’s high.  


S.T.S.'s picture


This post is not entirely correct nor is it the most up-to-date. When searching something on the internet I encourage people not to waste time posting negative comments, but using their time to further their research. While it is importamt to look at all sides and consider all opinions, too many people are bent on finding fault instead of offering support. Whether this author made mistakes is irrelevant. It is up to the reader to accumulate as much information from as many different primary resources as possible. Ergo, when you look up something online you must recognize it is not a primary source in most instances. Learn to read between the lines and extract pertinent facts, ideas, et. al. and then research those down to their core foundations and b;uild your understanding up from there. I think this author may be simply trying to say he hoped scientists could come up with a type of pain releif medication derived from serotonin in hopes that those in pain could alleviate their suffering without the possibility of forming addictions. That would be great wouldn't it? Problem there is that there is no way to eliminate addiction. Every human is addicted to something: drugs, alcohol, sex, lying, exercise, smoking, eating, spreading negativity, and on and on into infinity. We as humans simply trade one addiction for another throughout our lives. It's just life. It's unfortunate that in the hopes of improving quality of life by eliminating pain and suffering there is a dark side, and I wish society perceived things differently. However in the end we must remember that all of us, regardless of which side of the argument you take, are only human in the end. We choose to live in society and form government for our collective wellbeing, but there is a downside to that. In exchange for the benefits we must endure the drawbacks as well, and sometimes that means your neighbor is all up in your business. In a larger framework that means that the greater the society size the greater the number of neighbors. Eventually you have a society where the neighbors get together and form groups and in a collective democracy that means everyone (or every group) may interject their opinions into the discussion. If we are going to live together for collective benefit we must deal with listening to opinions that differ. Some people or groups take that to extremes unfortunately. In the end it's like anything else in the universe: for every action theie exists an opposite reaction. An opinion for or an opinion against; effects or side-effects; peace or disturbance; being together or being alone. In the very end it doesn't matter what government does or says or what the group or neighbor thinks or does because are born alone and die alone, and only we as individuals are the final arbiter deciding through our actions or inactions for what happens in between. We as intelligent beings will always find alternatives for everything. It's up to us to decide, hopefully after due consideration, how we live our lives. Pain, whether it be physical, emotional, or other, is part of life. We decide what we can and cannot tolerate, then we act according to our will. Fight or flight; fate or free will. (I will add that someone will certainly twist my words into something else--maybe that I am advocating for or against something. I am not. I am simply saying life is what we make it. I could've said when life gives you lemons you make lemonade or you go without vitamin C and deal with scurvy. Who knows! I know things get tough, I just think positivity rather than negativity makes all the difference--good or bad.)

Denday's picture

This is a great topic and

This is a great topic and very important And relevant for every person to consider that their own mind and body can deal with the challenges of life without extracted and synthetic compounds to rely on. This comment by the way was amazing, such a wholistic and broad perspective without being boastful or bias just enlightening and inspirational, thank you! (S.T.S)

Serendip Visitor SittingMoose Shaman's picture

The Body's Natural Painkillers

- I'm a med-bed ridden disabled person suffering from degenerative disc disease, spinal stenosis, and other related malaise.
I can barely walk, I use a walker...when going to the doc's appointments. I'd use my wheelchair. However, my lower spine is in bad shape and sitting has become nearly impossible.
"Vigorous exercise." !?! I once was a super-jock! Rode my Raleigh Altimetric everywhere. To & from work, all over town & country. Wife used the car for her job. I even rode to the jock shop's, free weight & circuit training room and followed a strict football player's regimen for a defensive lineman. Ate a planned, weekly menu of freshly prepared foods. Absolutely, no "processed" anything...Jack Lalaine succeeded. Well, I tried.
Diseases are a human's internal/external personal/societal disaster. And the gnat-see Gestapo wannabe's of the DEA are directly attacking the pain patient's UN's Declaration of Montreal: Fundamental Human Rights to opiates for pain management treatment of incurable/permanent and/or death-sentence malaise. So, with lies of "abuse" & "addiction" spread through the politically correct, party rat-finks & the party-controlled USA's media, which support the District of Columbia's NAtional soCIalist agenda. The MANY, MANY D.C Gestapo goosers in locked-&-loaded fashion, shoot crippled citizens onward as they try to march America into the gnat-see elite's vision of America: The Police State.
Your regimen is ok...for people who are...physically, ok. And that's it.
Political zealotry and propaganda techniques gleaned from the beasts of dictatorships past is the promotional heart of disingenuous appeal.

Serendip Visitor's picture

Runners high

The runners high is from anandamide... an endocannabinoid. Our body makes 6+ cannabinoids... cannabis plant has 66+ cannabinoids...

Cannabinoid Receptors are in the body CB1 and CB2
More info on this system here..

Peter Simmons's picture


You wrote: When the body is subjected to a stress, such as a continuous workout at a level on intensity between moderate and high, a peptide is produced in the pituitary gland and hypothalamus is released into the central nervous system [1]. The hypothalamus is a portion of the brain that contains a number of small nuclei with a variety of functions. It is not a peptide released into the central nervous system. Further, you list methadone as an opioid, it is a synthetic drug not derived from opium, although you could have put codeine, that is an opiate.
Howard Becker doesn't know what he's talking about when he posits about maijuana, the effect is immediate and pleasurable, there's no learning how or learning to connect, what an idiot, and sad yo chose to quote him, the fifties??? I see this is dated 2007, I hope you've moved on and improved your knowledge in the last six years.
6 out of 10.

Moreaccurate's picture

I agree with Howard Becker's

I agree with Howard Becker's analysis. You do have to learn how to use it, you do have to attribute the effects of marijuana to marijuana, and lastly you either attribute a positive or negative effect to the drug, if pleasurable you may or may not continue to use that drug. All in all, Howard Becker's analysis of the process is accurate enough.

James's picture

Pain Chronic

This disease is painful and people suffering from it suffers greatly by the constant pain caused by taking medications that are opioids narcotics such as Codeine, Lortab, Vicodin, hydrocodone, which are very effective in suppressing the pain that causes the disease, we hope that people care and know findrxonline adequately informed as well as notes on your site.

psoriasis homeopathy's picture

Accupressure and Accupuncture

the best pain killer of the body are the pressure points itself present in the whole body specially in our palms and leg palms,this therapy is called the acupressure and similar sort of therapy is called acupuncture where some punctures were made to body threw sharp pins,but this therapy is very painful hence refer to acupressure you will get lot of stuff in the web easily.

kenny brandt's picture

treatment refractory depression

I ,unfotunately,belong to this much misunderstood group of 'no reasons to live'. we account for about 20% of the mental community.I never hear about all the studies and research involving the very possible role of medicines that work with our opiate receptors. Too mamy chicken shit doctors.That group I belong to,god only knows how much hertaches and unbearable letdowns we might have ...well at least we could have brought light ,hope and actual help into our very lonly and sometimes ANGRY cut off lives.Buprenorphine is one of the medicines being touted for its possible role in several psychiatric afflictions.Now heres the catch......It's too damn expensive for our tax paying citezens to be footing the bill for those of us who could not even begin to afford the cost of the very drug that might [for some of us , the very first time to actually experience the awesome reality of a simple conversation that actually had so much meaning.....etc Little things you probably take for granted are the very things many of us have tried so hard to belong ...and now,if you will please help us sir...sincerely,kenny brandt

Theresa's picture


Hi Kenny,
I'm not going to pretend to understand what it is you're dealing with. I came upon this article looking for alternatives for pain management (after a car hit me in January, I've had 9 operations and a ton of anaesthetics and painkillers pumped into my body).
The reason I'm replying is that some of the things I've found may be worth you investigating if you will consider the alternative health arena. I'm actually getting some fantastic results healing my leg (it's a major mess!).
So, if you are interested, I haven't fully investigated this one yet, but the site says there is treatment for depression. This is about "tapping" which I have used previously and effectively on strong fears. And you could also try Google Videos - type in "grandmaster david harris spiritual healing".
I wish you well Kenny and hope that you find something affordable to help you improve your quality of life.