Please ensure Javascript is enabled for purposes of website accessibility Caffeine: King Of Psychostimulants! For Mental & Physical Performance

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science nutrition <strong>blog</strong>

By: Robert A. Schinetsky


 Stimulants -- a substance that increases levels of physiological or nervous activity in the body

 As a species we love our stimulants.

 One need only look at the most widely consumed drug in the world -- caffeine -- for proof-positive that humans love them some stims.

 While caffeine intake varies from country to country, and region to region, in the U.S., recent estimates note that upwards of 90% of adults consume caffeine daily[1], with an average intake of approximately 180mg per day -- that’s about as much as you’ll get in two cups of brewed coffee.

 Given the enormous popularity of caffeine, let’s dig a little deeper into what caffeine is and why you absolutely should consider using it.

What is Caffeine and What Does it Do?

 Caffeine is a xanthine molecule naturally occurring in coffee, tea, and cocoa that acts on the body’s cells via multiple mechanisms of action across a wide range of molecular targets.

 First and foremost, caffeine antagonizes adenosine receptors. This means that caffeine binds to adenosine receptors, which prevents the actual adenosine molecule from binding to its partner receptor. Adenosine is a neurotransmitter than promotes feelings of tiredness and lethargy. By antagonizing adenosine receptors, caffeine promotes wakefulness and alertness.

 Secondly, caffeine inhibits phosphodiesterase (PDE) enzymes. Yes, in case you were wondering, PDE enzymes are the same family of enzymes that are the target of male enhancement products, such as Viagra and Cialis.

 Thirdly, caffeine acts as a sensitizer of calcium liberation channels, which means that caffeine increases the release of calcium, which we’ll explain why that’s important a little further on in the article.

 Caffeine also antagonizes GABA receptors[2]. In case you weren’t aware, GABA is one of the primary inhibitory neurotransmitters in the body, so by antagonizing these receptors, caffeine in a sense blocks GABA molecules from binding to their parent receptors, therefore enhancing excitement and arousal.

 Finally, caffeine also affects the cardiovascular system in a number of ways, which relate to blood flow and, more specifically nitric oxide production, and with that taken care of, now let’s get to the real meat of the matter... 

Why Should I Take Caffeine?

 Simply put, caffeine is the single most studied performance-enhancing drug on the plant, with hundreds and hundreds of research papers documenting is safety and efficacy for improving everything from cognition to athletic performance and even longevity!

 But, it that’s not thorough enough for you of an explanation, allow us to go a bit further into detail...

Stimulates Central Nervous System

 The main reason people consume coffee, tea, pre workout, amino energy supplements, or No-DOZ is for the caffeine, pure and simple.

 As a powerful central nervous stimulant, caffeine wakes you up, helps clear the cobwebs, and makes you feel somewhat “normal” after a terrible night’s sleep. In a sense, caffeine is there to kickstart your brain into gear when it’s puttering about.

 Caffeine increases energy and alertness primarily through its antagonism of adenosine receptors and stimulation of dopamine receptors. The combination of increased dopamine and reduced adenosine binding leads to increased feelings of alertness, motivation, focus and energy, even when using doses as low as 32mg.[3]

 As a result of this CNS stimulation, you have the energy and motivation to get things done with greater efficiency and enthusiasm. Those “things” can include anything from studying for a test, to finishing a presentation for work, or getting in the gym and going ham on the weights.

 And that brings us to the next reason you should supplement with caffeine, which is...

 Enhances Exercise Performance

 If we had to choose one, and only one, supplement to take prior to training, it would hands down be caffeine.

 The vast amount of research proving caffeine as an ergogenic is simply too massive to ignore, and if you’re looking to up your game in the gym or on the field, you need to seriously consider adding caffeine to your supplement protocol if you’re not already using it.

 What makes caffeine such an effective performance enhancer?

 - It reduces perceived effort, meaning consuming caffeine makes training feel easier[5]

- Caffeine enhances resistance to fatigue, particularly when engaged in high-intensity exercise protocols such as cycling or sprinting[6]

- It can reduce poor training performance due to sleep deprivation as well as exhaustive exercise [6]

- Caffeine increases the number of reps you can perform before succumbing to fatigue and failure.[7]

- It even boosts power output, strength, and muscular endurance[8,9,26,27]

- Caffeine also increases fat burning during exercise, which means that glycogen is spared for later in the workout when you really need it to push hard on those last few reps.

- Recently, caffeine has been found to enhance glycogen resynthesis during the recovery phase following exercise[6]

 Basically, caffeine enhances your performance in just about every way possible. Let’s also not forget that taking caffeine also helps increase energy, focus, and motivation, which also further improves your ability to perform well in your training session.

 How much caffeine do you need to take to get these benefits?

 The general consensus as noted by researchers suggests that the ideal dose for caffeine pre workout is between 3-6mg/kg.[10,11] For the average 180 pound (~82kg) male, the amount of caffeine they would need to consume to get the ergogenic effects of caffeine would be between 245-492mg.

 And, one other thing to point out in regards to maximizing caffeine’s effectiveness during training -- when should you take it.

 Far too often, lifters slam their pre workout mere moments before walking into the gym and then get right to work. But, here’s the problem.

 While you might “feel” some of the effects of caffeine around 15 minutes after taking it, it takes between 30-60 minutes to reach peak concentrations in the body. In other words, if you want to get the most bang for your caffeine buck, take your pre workout at least 30 minutes, and preferably 45-60 minutes before starting your warm up.

 Now, remember, the ability to tolerate caffeine and how it impacts an athlete is highly individual. Therefore, if you’re not used to taking caffeine, absolutely start on the lower end of the spectrum and assess how your reaction is before considering any increase in dosage. Other factors that will influence your response to caffeine include:

- Height

- Weight

- Genetics

- History of use and amount used daily

 Lastly, let’s not forget that the neurotransmitter dopamine plays a crucial role in exercise performance, too. During intense training, dopamine levels become depleted, which decreases motivation and increases fatigue. By increasing dopamine (via caffeine consumption), you can maintain a high level of performance, stave off fatigue, and reach new heights of athleticism. This boost in dopamine can be enhanced further by the addition of ingredients such as L-Tyrosine, L-Dopa, and Folic Acid, which support the dopamine production process and help ensure your body has all the “building blocks” it needs for optimal dopamine synthesis.

 Due to the importance dopamine has for superior athletic performance, we’ve included each of these ingredients alongside caffeine in AML Pre Workout and AML Amino Energy

Elevates Mood & Motivation

 As you probably know, dopamine is one of the body’s primary happy hormones/neurotransmitters, and it plays a rather significant role in mood and motivation[12]’s called the “reward molecule” and “motivation molecule” for a reason.

 Basically, without sufficient dopamine you don’t feel like doing much of anything, and you won’t find much pleasure in anything you can bring yourself to do, either.

 Caffeine is an incredibly powerful dopamine agonist, meaning it stimulates your dopamine receptors, creating a cascade of the happy molecule in your brain and heightening mood and motivation.

 Research backs this up too, as numerous studies show that caffeine boosts mood and in those people who regularly consume caffeine from coffee or tea have lower rates of depression.[13,14]

Improves Mental Performance

Ever struggle to find the right words, or lack the ability to really dial-in focus and learn some new material?

 Great news!

 Caffeine can help there too.

 Studies note that caffeine is an incredibly powerful cognitive enhancer. One that increases:

- Focus[15]

- Memory[16]

- Alertness[17]

- Psychomotor learning speed[18]

- Reaction time[19]

 It can even improve performance following sleep deprivation.[6] So, if you know you’re in store for some mentally demanding work, having a cup or two of coffee (or a serving of AML Dopa Rush) can go along way to ensuring you’ve got the mental fortitude to power through it. 

Boosts Nitric Oxide

 One of the longest running myths about caffeine is in regards to effects on the cardiovascular system -- namely that it increases blood pressure and reduces blood flow. However, upon further inspection you’ll see that these effects are transient, meaning they are short lived. Long-term studies on individuals regularly consuming caffeine note it does not lead to hypertension (high blood pressure).[20,21] 

In fact, caffeine (and coffee as well as tea) may actually improve blood flow, due to caffeine’s ability to act directly on endothelial cells, stimulating the production of nitric oxide.

 The actual process by which caffeine does this is a bit complicated, but we’ll do our best to explain it briefly...

 Caffeine stimulates the release of calcium ions from the endoplasmic reticulum, prompting an increase in intracellular calcium in the cytoplasm. This release of calcium leads to the formation of calmodulin (a calcium-binding messenger in our cells) which supports activation of endothelial nitric oxide synthase (eNOS), resulting in nitric oxide production.

 Under “normal conditions” (i.e. no caffeine), there is only a moderate amount of calcium in the cytoplasm. It’s typically not enough to activate eNOS. However, researchers believe that caffeine lowers the threshold required for the “calcium-induced calcium release” mechanism. What this means is that when you consume caffeine, the amount of calcium required to activate this mechanism is lowered.[22]

But there’s more….caffeine not only directly stimulates nitric oxide production, it also “indirectly” supports it through a few mechanisms, including[23]:

- Caffeine inhibits phosphodiesterase (PDE) enzymes, which prompt an increase in cAMP levels. cAMP (cyclic adenosine monophosphate) increases “non-contractile” calcium (Ca2+) and concurrently lowers cytoplasmic Ca2+ (iCa2+).

- Caffeine also inhibits Myosin Light Chain Kinase (MLC Kinase). As a result of this inhibition, MLC phosphatase dominates, resulting in vasodilation.

- Caffeine inhibits inositol triphosphate (IP3). In case you weren’t aware, IP3 causes the sarcoplasmic reticulum to release calcium ions (Ca2+), which is needed for constriction of blood vessels. However, since caffeine inhibits IP3, so too does it prevent vasoconstriction.

 Basically, any way you look at it, caffeine not only doesn’t restrict blood flow, it directly and indirectly enhances blood flow due to its stimulation of nitric oxide and inhibitory action on enzymes that limit blood flow. 

Supports Fat Burning

 Caffeine enhances resting energy expenditure, which means that even when you’re doing nothing at all, your body is burning more calories than it normally does when you’re consuming caffeine.

But that’s not all, caffeine also helps your body actually burn more body fat as well.

Research involving obese as well as lean individuals documented that consuming 100mg of caffeine (the same dose used in AML Amino Energy) increased energy expenditure up to 150 calories per day![24]

 Other research has noted that caffeine can help suppress appetite.[25] Weight loss is a function of calories in vs calories out. So anything that reduces the number of calories you ingest or increases the number of calories you expend, enhances weight loss.

 The beautiful thing about caffeine is that it does BOTH! It can help lower your appetite and speed up your metabolism, supporting fat loss from both ends of the spectrum.

 And, if you use caffeine before you workout, you will be able to train harder, further increasing your “calories out” and accelerating fat loss that much more!

Increases Longevity

 If for no other reason that you should consider using caffeine, then consider this -- consuming caffeine may increase longevity and lifespan.

 A recent involving 4,863 people with chronic kidney disease noted that those who regularly consumed more caffeine were about 25% less likely to die from kidney disease or any other cause during the 10 year study period than those individuals who consumed less caffeine.[28]

 Researchers attributed these effects to a number of things, but in particular was caffeine’s ability to enhance nitric oxide production and improve blood flow in the body.

 A separate 10 year epidemiological study, involving half a million people, noted an inverse relationship between coffee consumption and risk of mortality.[29]

Caffeine vs Other Psychostimulants

 Given all of the benefits attributed to and associated with caffeine intake, some of you reading this make the assumption that if one stimulant is beneficial for you, then others must be as well.

 However, we’d advise you to exercise a modicum of restraint with your use of stimulants beyond that of caffeine, as… 

Not all stimulants are created equal.

 A lot of pre workouts (as well as fat burners) on the market use a crazy combination of stimulants with little to no human safety data. Nevermind the fact that these same stimulants are also lacking a robust body of evidence detailing their ability to enhance performance. Yet, countless pre workouts on the market use these stimulants all the time.

 It just doesn’t make sense.

Sure, taking a pre workout with five or six stimulants might feel great at first, but there’s guarantee your performance will benefit or that you won’t experience some kind of horrendous energy crash shortly after taking them.

 This includes all manner of other stimulants commonly found in pre workouts and fat burners, including, but not limited to:

- Higenamine

- Hordenine

- 2-aminoisoheptane (DMHA)

- Eria Jarensis (n,n-dimethylphenethylamine)

- Halostachine

Yeah...But What About the Tolerance Build Up?

 Many of you reading this might be wary of caffeine for no other reason than that it you can develop a tolerance to and dependency on it. While it’s true that these two issues exist, the degree to which each one affects you personally depends on a complex melange of factors that make each person’s experience on caffeine, and its withdrawal, very different.

 Some people can not take caffeine for a day and feel perfectly fine. Others might try to cycle off caffeine for a couple of days and experience slight feelings of lethargy, drowsiness, or irritability. There’s no universal experience for every person.

 And, if you’re worried about developing a tolerance to caffeine’s performance-enhancing effects, relax.

 Research has shown that even in habitual caffeine consumers, consuming some caffeine prior to exercise still results in improved performance[30,31,32]. So, if you’re a person who likes to have a cup of coffee or two per day, you can still derive benefits from taking some caffeinated pre workout before training.


 Taurine is an conditionally essential amino acid routinely included alongside caffeine in numerous pre workouts and energy drinks. Taurine serves a number of roles in the body. It maintains cell volume, supports muscle contraction and enhances antioxidant defense systems in skeletal muscle.

 Based on this, you might wonder why we caution against stacking taurine with caffeine. Well, that’s do to a couple of reasons.

 First and foremost, multiple human studies have noted that the combination of taurine + caffeine DOES NOT improve energy, performance, or attention.[33,34,35,36]

 It does, however, increase feelings of fatigue, reduce feelings of vigor, and lessent the stimulating effects of caffeine, which brings us to the second point…

 Taurine is a powerful activator of GABA receptors in the body.[37] In case you weren’t aware, GABA is the main inhibitory (“downer” neurotransmitter in the body, which signals to your brain it’s time to wind down, relax, and chill out.

 Essentially, stacking taurine and caffeine is a perfect way to rob caffeine of its stimulating qualities and energy boosting effects. So, by all means, if you want less energy, productivity, and arousal from your caffeine, then by all means continue to use taurine and caffeine together.

 But, if you enjoy caffeine for what it is and what it can do for you, nix the taurine.

 Due to these factors, you will find NO TAURINE in either AML Pre Workout, AML Dopa Rush, or AML Amino Energy!


 When taking everything into account, there really is no question or debate…

 Caffeine is the undisputed KING of stimulants.

 When used appropriately and within reason, caffeine can be a phenomenal addition to your day to enhances productivity, energy, mood, motivation, and performance. There’s simply no good reason to completely avoid it, unless you’re extremely sensitive to it. But outside of that, you have far too much to gain to not include in it some way, shape, of form in your daily supplement regimen.




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