I love to exercise. I know to some people this might seem foreign, but I love to exercise. I love to do resistance training. I love to run. I am not one of those people that doesn't like the experience of exercising, but likes the feeling afterwards, quote unquote. I hear that a lot.

I don't like to exercise, but I love the way I feel afterwards. I love physical training, and I love the way I feel afterwards, but I mostly love the feeling during. I don't know why I'm wired that way. I can't say that I'm somebody who likes to do hard things across the board.

There are plenty of difficult things in life that I dread or that I'm sort of meh about, but for me, hard exercise, intense exercise of a particular kind, resistance training and running in particular, both give me a yum, yes. I love this kind of feeling. And yes, it persists for me quite a long while afterwards, both for sake of the way that it changes my neurochemistry, but also my sense of satisfaction, but I just simply love it.

Now, years ago, I discovered that if I drink a cup of black coffee or an Americano or a double espresso or some yerba mate, that my workouts can be quite a bit more intense. I can run further. And then I also discovered that if I were to take a pre-workout energy drink, or I took, say, 300 milligrams of alpha-GPC and 500 milligrams of phenolethylamine, and perhaps even 500 milligrams of L-tyrosine, and perhaps did that alongside the caffeine and the yerba mate, then yes, absolutely.

I really liked those workouts. I could be like a laser in terms of focus. I could exert even more effort, put on some music, and I could achieve even better performance. And then I also discovered that I could export that protocol of caffeine, yerba mate, and various supplements to my cognitive work.

So when I was studying or writing papers or writing grants or in the laboratory, when I was doing experiments with my hands in those days, cutting brain tissue and staining it and working really long hours, and I discovered that all of those things, all of those behaviors compounded with my love of exercise and my love of doing science and gave me these big peaks in what, to me, felt like even important experiences.

They felt, you know, unlike anything else. They were just so, so peak in their nature, which was great, and it did indeed enhance my performance. However, while it did not create a dependency for those different substances, caffeine, supplements, et cetera, what I noticed was that in the days and sometimes weekends afterwards, even though for much of my career, I confess I've worked weekends as well, but I would notice that I'd experience a real trough in energy.

I just would not feel that good. And then if I kept up those behaviors consistently and I was consistently adding in these other, let's just call them what they are, dopamine-releasing or stimulating behaviors and substances, that my enthusiasm for physical training or running or for doing experiments actually started to diminish.

And this was really discouraging to me at the time because I started to think, okay, maybe I'm burnt out. Maybe I have adrenal burnout, which by the way, doesn't exist, folks. Your adrenals don't burn out. There is something called adrenal insufficiency syndrome. You can overstimulate your system by way of too much adrenaline, epinephrine, and norepinephrine, but that's a separate thing.

There's no such thing as adrenal burnout per se, but I didn't know that. So I thought, gosh, I'm really burnt out. When in fact, it's now obvious to me what I was doing. I was combining too many dopamine-releasing or stimulating behaviors and substances for things that I already enjoy doing as behaviors, namely exercise and doing experiments, anything related to science, actually.

So what this means is not to avoid taking things or doing things that amplify your amount of dopamine, but to be very cautious about how often one does that and how many different dopamine-stimulating behaviors or compounds one stacks, especially in terms of taking those things or stacking those things in and around behaviors that you already really enjoy doing.

I was essentially just creating another version of the kids in nursery school or first grade with the Gold Star experiment. I was basically just doing the exact same thing. And when I realized that and I changed my relationship to those compounds, I didn't eliminate them altogether, but I started realizing, for instance, that I didn't need to double up on yerba mate and coffee every workout.

Sometimes I would do one, sometimes I would do the other. Frankly, I always do one or the other. It's rare that I ever do any kind of physical training without some caffeine first. And I do my physical training typically in the early part of the day, so that's fine.

It doesn't interfere with my sleep. I might do a hike without caffeine, but if I'm in a weight trainer, I'm going to run. I tend to drink coffee beforehand or have yerba mate. Or if I occasionally, meaning about once every third, sometimes every other, but usually about every third workout, I'll take 300 milligrams of alpha-GPC.

Maybe occasionally, maybe every third or fourth workout. And these are resistance workouts, mind you, not running. I'll take 500 milligrams of l-tyrosine or more typically 500 milligrams of phenolethylamine. And very, very rarely, maybe once every two or three months, I might stack all of those things together prior to a workout.

But of course, I'm always mindful to also include workouts or runs or bouts of cognitive work. So that could be grant writing, prepping for a podcast, et cetera, where I don't do anything prior. Maybe just my caffeine because I have a baseline level of caffeine that I use each day to function.

Like many people, there's a baseline level of caffeine that just allows us to function if we're a perpetual user of caffeine. I talked a lot about this on the episode in caffeine. But the key here is be cautious. I would say be very cautious about stacking and layering in too many dopamine peak inducing behaviors all at once on a regular basis.

The key point here is if you are somebody that can engage in these intrinsically joyful activities for you, these activities that you're really motivated to do, whether or not it's skiing or playing music or dancing, et cetera, without the need to layer in additional dopamine releasing mechanisms or compounds or activities, well then I highly recommend you do that because then you are essentially making yourself one of those fortunate few that does not require additional stimuli and therefore can hold onto that pleasure, can hold onto that intrinsic pleasure and motivation to engage in these behaviors over time, which frankly there is no replacement for.

There is no pill or bottle or potion or motivational speech or podcast or book that can replace intrinsic motivation. Intrinsic motivation is perhaps the holy grail of all human endeavors and behaviors because it encompasses so much of what brought us to this point in our species evolution. And also what brings each and every one of us closer and closer to our goals.

And if it's happening with enjoyment without the need to layer in additional tools, well then you have really tapped into the source. And when I say the source, I don't mean in any kind of mystical way. I think it's quite clear by now that when we hear about chi from Eastern medicine or we talk about motivation, drive, and pursuit in Western neurobiological languages that relates to dopamine or we hear about the source, maybe in my podcast episode with the one and only Rick Rubin, incredibly productive music producer who's has just an unbelievable track record in terms of creative endeavors.

And he talks about the source. We're really talking about the same thing, which is this set of circuits within us that allow us to identify what we want and then lean into effort. And then to do that in a persistent way that allows us to reach our goals. And if we can do that with an intrinsic sense of pleasure, well, that is nothing short of magic.

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