Understanding the Runner's High

I’m a big fan of the runner’s high. For me, the euphoric feeling is unmistakable (and usually around mile 8), which is why I’ve always been confused by coaches and medical experts saying that the “runner’s high doesn’t exist”. If that’s true, then why are we all as giddy as school girls after our weekly long run? Is it really all in your head, or is there a chemical interaction that can explain it? I did some research on the subject just to make sure I wasn’t crazy and was surprised to find some recent studies that may have found the chemical link.

What Is The Experience of The Runner’s High?

For those of you unfamiliar with the runner’s high, I would encourage you to seek it out as part of your training. It’s a mental state of relaxation partnered with a mild pain cessation that occurs after 60-90 minutes of steady exercise. I find it truly euphoric, setting me in a state of eternal optimism that can last hours after a run. It’s not exactly a “drunk” effect, although it does make it a bit more difficult to remember to eat/drink/take the next turn (remember – always carry a map!). I would equate it to two Red Bulls and vodka, three ibuprofen, plus a $50 winning Lotto ticket in your pocket. ;oP Definitely not to be confused with bonking (when your glycogen has been depleted due to not keeping up your calorie intake), which is more like a half bottle of Jack Daniels when you have the flu, complete with blacking out to the mantra of “oh God, please kill me now”. I didn’t experience the runner’s high until about 5-6 long runs (unlike bonking, which I hit on day two), so give it some time.

The first time you experience the runner’s high, it can be a bit alarming. At first it feels like that mild head rush I associate with going anaerobic, but instead of fading, it builds over the next 5-10 minutes. I feared this "build" the first couple of times, wondering if I my water intake, electrolytes, or calories were out of balance. After realizing it consistently faded away, I convinced myself it was just a “wall” you had to push through when you depleted your initial glycogen levels, since 1200 calories occured in about 90 minutes for me, and I thought that was an average glycogen level for somebody my age.

I noticed that when I hit this state, my tempo runs became very even, even though I was spending more time looking around than looking at my watch. Everything had a natural rhythm to it - my footsteps, the sound of the wind running past my ears...even the trees and hills around me seemed to flow together. It was a wonderful meditative state. Before I knew it, I was longing to run 8-10 miles every day to “break on through to the other side” to find that familiar state. Hello, addiction!

Science Casts It’s Vote – It’s Like Smoking Pot!

For the majority of the last two decades, scientists have struggled with defining the chemical reaction associated with the runner’s high. It was largely believed that the sensation was caused by endorphins, natural opiates in the body that are produced after trauma such as running for long periods of time. Just one problem – endorphins are too large to pass through the blood-brain barrier, making it impossible for this chemical reaction to be the sole cause. But in early 2004, Dr. Daniele Piomelli (UC Irvine) and Dr. Arne Deitrich (University of Beirut and Georgia Institute of Technology, also a marathoner) found another possibility – anandamide, a natural chemical that stimulates the brain in the same way marijuana does.

[warning – I am no PhD, so what follows is my dumbed-down version of a ton of great research done by real docs; it probably doesn't help that I've already gone on my long run this morning]

Anandamide (conveniently named after the Sanskrit word for “bliss”) is a neurotransmitter produced in our brain that activates the CB(1) receptor, the same chemical receptor that is triggered by tetrahydrocannabinol (THC), the active ingredient in marijuana. Oddly enough, it was the study of the effects of marijuana that led to the discovery of the CB(1) receptor (thank you, stoners!). But one part was confusing - the body doesn’t create receptors that don’t have natural internal triggers (and marijuana being an external trigger), so there had to be a natural internal trigger somewhere. Thus the search began for the natural chemical that stimulated CB(1), which in turn led to the discovery on anandamide in 1992.

Piomelli and Deitrich, looking for the runner’s high connection, performed a study in early 2004 with two dozen college students who ran or bicycled for 40 minutes at 76 percent of their max heart rate, and then had blood samples drawn immediately after exercising. The results showed that both the runners and bicyclists had 80% more anandamide in their blood after exercising, with the greatest increase among the runners. They also reported physical feelings similar to marijuana use, such as relaxation, regulated mood, and increased appetite. Here’s the biggest kicker - tempo running produced the most anandamide of all exercise! Although more studying is required to really nail this down, it is clearly a big breakthrough on understanding the runner’s high.

On a side note, it also turns out that chocolate has small amounts of anandamide in it (Dr. Emmanuelle di Tomaso, 1996) as well as the ability to increase serotonin levels, both of which help regulate mood (ie, make you feel good). So, run every day and eat lots of chocolate to feel good? Me like!

Side Effects of Anandamide Use?

There is some supposition about whether the harmful side effects of THC (short term memory loss, low sperm count, reduced learning capabilities in youth, etc.) are also present in the natural stimulation of CB(1) from anandamide. There hasn’t been a lot of research in this area, so it’s hard to conclude anything definite. Most suggest that the heavy side effects of THC come from the fact that it is an “external agent”, causing the body to overcompensate, and that anandamide (as an internal agent) is more self-regulated. One example that is often cited is when marijuana users get a case of the “stupids” the day after smoking, whereas runners do not - with marijuana, the brain "overcompensates" to rebalance the body, and you have a different chemical effect. Running, you don't.

It's worth a bit more elaboration on the "overcompensation" effect, because it has a lot to do with why you feel "high" in the first place. The CB(1) receptor can trigger how your short-term memory works, and adjust it as needed. When the CB(1) receptor is triggered, the brain uses less “memory cache” - meaning you process feedback in little chunks and quickly move onto the next. This is a similar effect to what happens when your body goes into "fight or flight" mode - it adapts to get more data from its surroundings. This is why everything seems so new and exciting when you are “high” with marijuana. The “stupids” that marijuana users feel the next day is the body overcompensating and creating a memory cache large enough to have you staring into space for minutes at a time. The ability to trigger this memory is also one of the reasons both anandamide and THC are being investigated for use in treating Parkinson’s disease and schizophrenia.

Conclusion

So it looks like we’re not all crazy, and there is a scientific rationale for the runner’s high. Well, a theory anyway. It doesn't say much about that spiritual connection I feel when running through the forest (or a good piece of chocolate for that matter). But it might help explain why I REALLY feel great about 80-90 minutes into my run, and why I want to do it every day.

So go run. Eat more cholocate. And the next time you think about dissing that group of stoners smoking out in the park, remember that you have more in common with them than you think. ;o)

Isn’t research fun?

Have a good New Years, and happy running in 2005!

SD

P.S. - Be sure to also check out subsequent research I found here and here.