It all begins with an innocent little top rope in the gym. Grab a hold, step up, grab a hold, step up. As the distance from the floor increases, you look down and a little flutter of fear and excitement triggers your body to release some cortisol, dopamine, adrenaline, and other handy chemicals. You complete the climb and feel pretty darn good. Repeat that action a few more times and eventually it generates about as much excitement as climbing the stairs.
 
Next, you think to yourself, “Hmmm…maybe I should try a grade or two up.”
 
Next time at the gym you eyeball some harder routes. Yep, the holds are smaller. Your palms sweat a little as you select a route and tie in. You dip your hands in the chalk bag, grab the first hold, and wonder if all the holds are going to be that crappy. Your arms eventually get pumped, your anxiety level increases, chalk bag-dipping increases, fears of falling increases. Cortisol, adrenaline, dopamine, and the stress-response cascade are doing their thing.
 
After you reach the anchors and lower, you breathe a sigh of relief and start to feel pretty good again. Dopamine is going to a special, happy place in the brain called the nucleus accumbens (in case you were curious). But, over time, those gym routes at that new grade just aren’t cutting it. You might as well be at the library.
 
One evening, you notice the quick draws hanging from the gym wall, then a woman with well-defined arms and back muscles smoothly pulls the rope up between her legs and clips it into the draw. Lead climbing looks bad-ass. You think to yourself, “Hmmm…maybe I should try that.”
 
You sign up for a class and hop on your first lead. What you heard earlier in class about falling at least twice the distance above the last clip hits you as you approach the next clip. The stomach flutter intensifies into a bit of an intestinal grumble. A larger release of the fight-or-flight chemicals tell the body to dispose of non-essential items, like shit and urine. You pucker-up and move forward. At the end of the session, when you are safe and sound on the ground, you feel pretty dang good – gotta love that dopamine reward.
 
Onward, upward, harder, more risky. The gym leads to the great outdoors, where holds aren’t easily seen or are deceptive, climbing grades are unpredictable, rocks can crush you, falls can propel you into jutting rocks or ledges, poisonous critters can sting or bite you, ropes can get cut by sharp ledges, bolts can pop out, and unpredictability rules. The chemically-driven body doesn’t know the difference between leading that first outdoor 5.10 or being chased by a bear; To the body, both events are simply one step closer to death.
 
To protect us from death, dopamine gets converted to adrenaline, making our body move and giving the brain more attention and focus. When we are done and the danger is over, dopamine moves back into the reward system, giving us the giddy sensation of success and that feeling of “Again! Again!”
 
In an over simplification of our amazing body, dopamine is the central character in generating the feeling of pleasure (there are other players too). It serves a biological function to get us to repeat actions that are, hopefully, good for us (e.g. sex for love, bonding, and reproduction; eating and exercising for health and well-being; or, accomplishing a task for progress and survival). However, when dopamine is repeatedly triggered in ways that release high amounts, addiction can come into play.
 
In drug addiction, drugs can increase dopamine up to 10 times the amount that occurs naturally in the body. The brain likes this; it feels really good. But if you keep feeding the body dopamine-releasing drugs, the brain physically changes – neurons become less sensitive to the dopamine and, ironically, the number of dopamine receptors decrease (akin to the body trying to turn down the volume).
 
Over time, these changes result in the high not feeling as high with the same dose of the drug. Thus, it requires more to feel good again. If the drug is decreased or stopped, the physical changes generate withdrawal symptoms. In short, it sucks to be without it.
 
Although exercise can be addictive, via these same mechanism of flooding the brain with dopamine, exercise induced dopamine is a more “natural” response (if you will), where reward comes with time and effort. Other balancing bodily chemicals also come into play. Drug addiction, on the other hand, is a shortcut.
 
Reasonable dopamine release is not a bad thing. In fact, it increases behaviors like drive and perseverance. When done via exercise, it stimulates other “healthy” chemicals that lower blood pressure, improve memory, and decrease inflammation. Exercise, in fact, has been shown to help people with a drug or alcohol addiction to not relapse.
 
Unlike drug addictions, we are less at the mercy of our chemical reactions when dopamine is triggered by exercise. Fear and logic help keep us in check – e.g. choosing to take the PG-rated version of a route versus the X-rated version. (X-rated is when there is little to no protection and a fall means likely death). Repeated experience also provides us with practice managing fear, which reduces the stress (or fight-or-flight) response. As our strength and skills improve, the actual and perceived risks also decrease, again, reducing the stress response. (Having ongoing stress/adrenal responses is not healthy overtime, so it is good to learn to manage it.) Managing the stress response also manages the dopamine flood.

To top it off, simply having positive feelings of being stoked and excited have been shown to release dopamine and other good-for-us chemicals. So we do not necessarily have to do the harder, scarier climb to get the benefit from climbing. We simply need to enjoy it and give ourselves a pat on the back even when we finish that easy 5.6. 
 
But, each of us, with our own unique history and body, vary in the level of attention we pay to our internal safe guards or attempts to give ourselves high-fives for completing easy shit. Some people, for whatever reasons, emotional or physical, tend towards addictive behaviors. Psychologists and physiologists have evidence that exercise addiction exists. So, what does such an addiction look like? Big surprise, a lot like other addictions. It includes feelings of craving, withdrawal, and tolerance. A telltale sign is repeating the behavior obsessively to feel “normal,” doing it at inappropriate times (although I have a hard time thinking of when climbing is inappropriate, perhaps when giving birth), doing it to the exclusion of people you love, and doing it until it becomes self-injurious.
 
As I think about this list with respect to climbing, some of these are really difficult to quantify due to the nature of our sport. Climbing takes time and it often requires travel, which we try to squeeze into our precious time off. If we have a significant other that does not climb, we are faced with difficult choices, stay with him or her, or go climbing. At what point does going out and doing climbing cross the line into neglecting a relationship? Well, that answer is going to depend on so many different non-climbing-related factors. Or, is tweaking a finger because you were trying for a hard move self-injurous? I guess it depends. Sometimes shit happens. But sometimes we make shit happen. With drugs, addiction seems a little clearer. 
 
Whether or not climbing is addictive, if we keep getting back on the rock, the bottom line is, we ARE getting off on the dopamine rush. Our bodies are simply wired for dopamine and doing things that release it feel good. In my own justification of my love of…obsession for... addiction to? climbing (I married a climber so I don't have to choose between climbing and a loved-one), I can easily rationalize that there are far worse addictive things. As with all things in life, I guess if I keep it balanced, keep it safe, rest, smile, laugh, and don’t purposefully hurt myself or others, then it’s all good. I, for one, plan to climb on.
 
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