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science nutrition blog

science nutrition <strong>blog</strong>

By Robert A. Schinetsky 



“Athlete -- a person who is proficient in sports and other forms of physical exercise”

Athletes come in all shapes, sizes, and levels of competition. 

Regardless if you’re a top tier physique athlete, world class strongman, or weekend warrior, if you’re putting in the work in the gym or on the field, you are an athlete.

Over the years, Advanced Molecular Labs has made it its mission to develop premium-quality supplements to support the needs of athletes.

Nowhere is this better showcased than our flagship AML PreWorkout supplement.

Formulated using ingredients backed by hard science, AML PreWorkout was a revelation to the pre workout landscape when it debuted at a time that was dominated by pixie-dusted, prop blends.

Since its inception, AML PreWorkout has been the pre-training supplement of choice for athletes of all walks. 

But, as we said, athletes come in all shapes and sizes, and there was a desire for more

  • More energy
  • More performance
  • More focus
  • And more


Out of this thirst for an edgier, harder-hitting pre workout arose AML PREWORKOUT X-Treme!

What is AML PreWorkout X-Treme?

AML PreWorkout X-Treme is the most advanced scientifically-based pre workout supplement ever developed.

As with all Advanced Molecular Labs products, AML PreWorkout X-Treme is based on the latest cutting-edge performance nutrition, research, ingredients and quantities. 

AML PreWorkout X-Treme is designed to support increased energy, mental alertness, muscular endurance, strength, and lean body mass.

It is for the serious athlete and fitness enthusiast, well versed in hard training, proper nutrition, and what makes a quality pre workout.

Let’s take a deeper look into what makes AML PreWorkout X-Treme a pre workout unlike any other.

What’s in AML PreWorkout X-Treme

Citrulline Malate 2:1

AML PreWorkout supplies 8 grams of Citrulline Malate, a proven ergogenic aid that supports blood flow and athletic performance.

AML Pre X-Treme ups the ante boosting Citrulline Malate to a heaping 10,000mg per serving!

At a 2:1 ratio of citrulline to malic acid (malate), that means you’re getting over 6,000mg of pure L-Citrulline per serving!

Why is this important?

L-citrulline is an amino acid that has been found to be a more bioavailable and effective nutrient for increasing plasma levels of Arginine (the “fuel” of nitric oxide production in the body), compared to L-Arginine supplementation.[1,2]

Not only is citrulline more effective than L-arginine, it’s also easier on the GI system than l-arginine, too.[2]

Human studies using citrulline malate note that it may help increase the number of repetitions performed while also reducing an individual’s rate of perceived exertion (RPE) versus.[3,4,5]

Research also indicates that citrulline malate supplementation may help reduce muscle soreness up to 40% in the hours following training.[5]

Citrulline also plays an important role in ammonia buffering, which in turn helps reduce lactic acid accumulation as well and boost exercise performance.

Creatine Monohydrate

In the annals of sports nutrition, there has yet to be an ingredient as rigorously tested or consistently shown to be beneficial than creatine monohydrate. 

Quite simply, it is the king of sports nutrition supplements.

The problem with creatine in the vast majority of pre workouts is that it is woefully underdosed.

That’s not the case with AML PreWorkout X-Treme.

Like its predecessor, AML PreWorkout X-Treme supplies the full 5,000mg dose of creatine monohydrate in every serving.

Multiple studies, reviews, and position stands have noted that creatine supplementation is effective for improving energy production, power and strength output as well as supporting lean mass gains.[6,7,8]

Typical protocols for creatine supplementation advocate consuming between 3-5 grams per day everyday in order to reach saturation and derive the benefits of creatine. 

However, a recently published study even found that even when creatine is only supplemented on training days, individuals experienced greater gains in strength and endurance compared to placebo.[8]

Beta Alanine

Beta alanine is the ingredient more than any other that is synonymous with endurance.

A nonessential amino acid, beta alanine binds to L-Histidine (another amino acid) to form the powerful intracellular buffer, carnosine.

When muscles repeatedly contract, hydrogen ions (H+) begin to accumulate, and as these ions build up, the muscle pH becomes more acidic, which eventually prevents the muscle from continuing to contract.

Beta alanine is the rate-limiting precursor to carnosine synthesis.[9]

Supplementation with beta alanine increases carnosine concentrations in skeletal muscle tissue, thereby improving a muscle’s capacity to buffer H+ ions and delay the onset of fatigue. This helps athletes complete more repetitions and more total work before succumbing to fatigue.

AML PreWorkout X-Treme contains 3,200mg beta alanine per serving, compared to the 2000mg dose contained in AML PreWorkout.

Betaine Anhydrous

Betaine (trimethylglycine) is a natural osmolyte found in a number of foods common to the diet, including whole grains, shellfish, spinach, and sugar beets.[10]

It plays a key role in several aspects of human health, including the methylation of homocysteine.

In case you weren’t aware, research indicates that high levels of homocysteine can be a risk factor for heart disease.[11]

maintain cell volume and fluid balance during stressful situations such as dehydration.

Additional studies have noted that diets high in betaine may also decrease the risk for certain diseases.[10]

As an osmolyte, betaine also helps maintain cell volume and fluid balance, which may help guard against dehydration during stressful events such as intense exercise.

Betaine also increases intracellular water[12], which encourages cell volumization and cellular swelling. This promotes muscle growth by way of stimulating muscle protein synthesis.

Lastly, a growing body of literature finds that betaine supplementation may significantly increase anaerobic power, muscle protein synthesis, and body composition.[12,13,14,15,16]


Motivation can be elusive at times, especially on those days when life gets hectic and/or sleep is in short supply.

That’s one of the many benefits of pre workouts supplements -- they can provide the “liquid motivation” needed to get in the gym and crush it, even when you’re not feeling it.

L-Tyrosine is an amino acid that supports biosynthesis of the “motivation and reward” molecule, dopamine, as well as several other highly important neurotransmitters including epinephrine (adrenaline), and norepinephrine (noradrenaline).

Supplementing with L-tyrosine supplies the body with additional “raw material” to synthesize these highly important neurotransmitters during stressful situations, such as a high volume leg workout.

Dopamine isn’t just about reward and motivation though, it also plays an important role in mood, memory, and motor control.

Deficiencies in the neurotransmitter can impact motivation, performance, mood, and cognition.

Stress (such as intense exercise) can also lead to reductions of dopamine stores in the brain, leading to increased fatigue and reduced athletic performance.[17]

AML PreWorkout X-Treme contains 2,000 mg of L-Tyrosine -- the same dose shown in human research trials to boost mental and physical performance as well as aid memory.[17,18,19]

Beet Root Extract

To further support blood flow and complement the actions of citrulline malate, AML PreWorkout X-Treme contains a formidable duo of plant-based extracts in beet root extract and grape skin extract.

These botanical extracts are rich in antioxidant compounds that have been shown to support NO production and blood flow for increased athletic performance.

Peak ATP

ATP is the cellular currency of energy production. The more rapidly muscle fibers can regenerate ATP stores, the longer they will be able to maintain a high level of performance and resist fatigue.

This is one of the main reasons athletes supplement with creatine monohydrate -- it increases a muscle’s ability to rapidly regenerate ATP.

Over the years, a number of exogenous ATP supplements have been explored, but by and large, they have failed (at least in humans anyway) due to a lack of bioavailability (even when using doses as high as 5,000 mg).[20,21,22]

Peak ATP® is a clinically-researched, patented form of adenosine 5’-triphosphate (ATP) disodium that is identical in structure to human ATP. 

Research has shown that supplementation with Peak ATP may improve athletic performance and body composition by increasing blood flow, muscular excitability, and recovery.

Studies note that Peak ATP® can provide benefit after just a single dose for increasing the ratio of muscle activation and power output during high-intensity exercise.

It may also help reduce protein breakdown and prevent performance drop-off as an individual gets deeper into their workout.[23,24,25,26]

The landmark Peak ATP study from 2013 conducted in humans noted[23,63]:

  • 147% increase in strength
  • 30% increase in power
  • 96% greater muscle thickness


Additionally, Peak ATP supplementation has been documented to reduce systolic blood pressure after aerobic exercise compared to placebo.[27]

Researchers also noted that ATP supplementation may help to potentiate the parasympathetic recovery after exercise, thereby encouraging faster recovery of HRV following exercise.[27]

AML PreWorkout X-Treme supplies the research-backed 450mg dose of Peak ATP in every serving.

Caffeine Anhydrous

If you’re looking for an X-Treme preworkout supplement, then chances are very high you’re well-acquainted with caffeine...perhaps even a bit too well-acquainted.

Caffeine is the backbone of all pre workout supplements.

It increases mental energy, focus, and motivation while also improving athletic performance and resistance to fatigue.

Perhaps, more importantly, caffeine has been extensively researched and not only proven to be effective for improving performance, but safe (when used in moderation).[28]

The same CANNOT be said of other stimulants commonly used in pre workout supplements, such as higenamine, hordenine, or PEA -- none of which are included in AML PreWorkout or AML PreWorkout X-Treme.

Caffeine’s main mechanism of action (and primary avenue of benefit) is via antagonism of adenosine, a neurotransmitter in the brain that induces feelings of lethargy and tiredness. By preventing adenosine from binding to its partner receptor, caffeine promotes increased feelings of wakefulness, alertness, and reactivity.

Caffeine also potentiates the release of dopamine in the brain as well as upregulates dopamine receptor availability and affinity.[29,30]

This is part of the reason why taking a pre workout that includes caffeine (or having a cup of coffee) seems to boost mood -- increased dopamine!

AML PreWorkout X-Treme contains the same 400mg dose of caffeine found in the original AML PreWorkout.

This dose is in line with research noting improvements in strength and power output in athletes.

TeaCrine 40%

Caffeine is renowned for its ability to impart a rapid infusion of energy, motivation, and focus. However, the half-life of caffeine is only around 5.5 hours.

TeaCrine is a chemical cousin of caffeine that complements the immediate burst supplied by the well-known stimulant by providing smooth, sustained energy.

TeaCrine is that patented form of theacrine -- a naturally occurring compound found in a number of plants, namely kucha tea Coffea robusta. 

TeaCrine works similar to caffeine, in that it affects both adenosine and dopamine receptors, but the manner in which it does so is slightly different than caffeine (which is why the two have a synergistic effect when taken together).[31]

This creates a “best of both worlds” approach to energy enhancement with caffeine providing the acute, powerful increase in energy and alertness and TeaCrine supplying a sustained, “slow burning” energy.

Research has shown that the combination of caffeine + TeaCrine favorably impacts endurance and the combination provides greater benefits on cognitive function than either supplement taken independently.[32]

Perhaps best of all TeaCrine does not come with habituation (tolerance build up), which means you get the same increase in energy, without having to continually increase the dose used (the same of which can’t be said for other pre workout stimulants).

AdvantraZ (P-Synephrine)

Advantra Z® is a patented extract of Citrus Aurantium (a.k.a. Bitter Orange), a fruit rich in a number of alkaloids known to support weight loss and exercise performance.

While citrus aurantium may contain a number of alkaloids, the one we’re primarily interested in is p-synephrine. 

p-synephrine is structurally similar to ephedrine but significantly weaker (which is a good thing). It’s been noted to increase energy expenditure, post exercise oxygen uptake, and fat oxidation, which lead to improvements in repetition performance and volume load during training.

Some other research indicates there is an additive effect when combining p-synephrine with caffeine.[33,34]

Specifically, combining caffeine with 100mg p-synephrine (the same dose included in AML PreWorkout X-Treme) was noted to help athletes achieve faster, more powerful repetitions all with no additional perceived exertion or lactate accumulation![33]

While p-synephrine is structurally similar to ephedrine, it is not the same compound, nor does it behave the same way m-synephrine does.

Both ephedrine and m-synephrine are banned substances in dietary supplements.

Furthermore, p-synephrine has virtually no binding affinity for α-1 and α-2 as well as β-1 and β-2 adrenoreceptors.[35]

p-Synephrine does, however, agonize the β-3 adrenoreceptor, which leads to increased metabolic rate and lipolysis, and it may also help reduce food intake. 

AML PreWorkout contains the research-backed dose of 100mg of p-synephrine (as AdvantraZ) which was noted to improve performance as demonstrated by increased total amount of repetitions, implying athletics who supplemented with p-synephrine exhibited increased muscle endurance.

AML PreWorkout X-Treme uses only the patented, quality-verified AdvantraZ.

Many other pre workout supplements on the market include generic citrus aurantium extracts, which typically contain between 6-8% p-synephrine.

However, a recent study found that many supplements utilizing generic citrus aurantium extracts did not meet label claims. Only 22% of the products tested actually contained the amount of synephrine they claimed.

Researchers also detected the presence of synthetic amines, including methylsynephrine and isopropyloctopamine, neither of which effects are well-studied in humans.[36]

Grape Skin Extract (30% Polyphenols)

As we mentioned above, AML PreWorkout X-Treme contains a pair of botanical extracts to complement and enhance the vasodilating effects of citrulline malate.

We’ve already covered beetroot, and now we shift the focus to grape skin extract. 

Grape skin extract is rich in a variety of polyphenols which have been noted to stimulate endothelial nitric oxide synthase (eNOS) and improve exercise performance.

Research indicates that supplementing with polyphenol-rich extracts may significantly increase average power (5%), total power output (5%), and maximal peak power output (3.7%).[37]

Additional research notes that supplementation with grape skin extract can reduce muscle damage after high intensity strength training.[38,39]

AML PreWorkout X-Treme contains 100mg grape skin extract (standardized to 30% polyphenols).

Velvet Bean Extract

Above, we discussed the importance dopamine plays in motivation as well as exercise performance.

And to support dopamine production during stressful situations, AML PreWorkout X-Treme includes 2,000mg L-Tyrosine.

But, this can be further improved by the addition of velvet bean extract, which contains L-3,4-dihydroxyphenylalanine (L-DOPA) -- the direct precursor to dopamine.

L-Dopa is naturally occurring in the body, and it’s also readily found in Velvet Bean (Mucuna pruriens).

Velvet bean has long been used in traditional medicine as a tonic and aphrodisiac due to its broad spectrum of activities.

Additionally, velvet bean has also been shown to be neuroprotective and exert analgesic (pain-relieving) and anti-inflammatory properties.[40]

Folic Acid

Continuing on with nutrients that support dopamine synthesis in the body brings us to Folic Acid.

This highly bioavailable form of vitamin B9 is required for the production of cofactor BH4 (tetrahydrobiopterin), thereby supporting the production of dopamine. 

Research notes an association between low dopamine levels (which are linked to depression) and low intakes of folic acid.[41]

Supplementing with folic acid supports dopamine production by providing the body with necessary substrate required to build the enzyme which is considered the “rate-limiting” step in the synthesis of dopamine.[42] 

You might also be interested to know that BH4 is an essential cofactor for the synthesis of nitric oxide.[43]

Essentially, folic acid is an important “support” ingredient often overlooked in other pre workouts that plays key roles in the production of both dopamine and nitric oxide -- both of which impact exercise performance.


BioPerine is the widely recognized, industry leading black pepper extract typically included for its ability to improve nutrient bioavailability. BioPerine is able to due this thanks to the presence of its primary bioactive, piperine, which inhibits the drug-metabolizing enzyme CYP3A4 as well as the drug transporter P-glycoprotein.[44]

Inhibition of CYP3A4 can help extend the “lifespan” of various nutrients, thereby increasing their efficacy and duration of effects.

Piperine also has been noted to increase dopamine via activation of the TRPV receptor in the brain.[45] 

Lastly, piperine also functions as a mild MAO inhibitor.[46]

MAO (monoamine oxidase) is the enzyme that breaks down mood-boosting neurotransmitters in the body, including serotonin and dopamine.

Inhibiting MAO may help dopamine levels remain elevated longer for greater energy, mood, and motivation!


Rounding out the comprehensive ingredient profile of AML PreWorkout X-Treme are the electrolytes -- magnesium citrate and potassium citrate. 

Electrolytes are essential for hydration as well as helping athletes avoid cramping and fatigue during training.

Additionally, potassium and magnesium also support cardiovascular health and athletic performance. 

Research notes that potassium can soften the endothelium and increase nitric oxide production.[47] 

Magnesium also causes vasodilation by increasing nitric oxide synthase activity.[48]

AML PreWorkout X-Treme uses the citrate forms of these essential electrolytes as they have been shown to be bioavailable and citrate has also been noted to improve exercise performance by buffering lactic acid buildup in the muscle.[49,50]

In total, AML PreWorkout X-Treme provides 1,000mg of potassium and 100mg of magnesium per serving.

The reason for these dosages is that research indicates that a significant portion of the population does not consume enough dietary potassium, and high potassium diets have also been shown to help lower blood pressure.[61,62]

More magnesium is not included because it can cause gastric upsetness and loose bowels in some individuals. 

What’s Not in AML Pre X-Treme

What’s not included in a pre workout is just as important as what is included in it.

Next, we discuss several common pre workout ingredients that you will NOT find in AML Pre Workout X-Treme.


Glycerol has long been used for its ability to promote a state of hyperhydration, due to its prominent osmolytic properties.

Endurance athletes most frequently add glycerol (in the form of a 20% glycerol solution) to their liquids consumed in and around training.

However, the research on glycerol and performance is mixed.[51,52]

Moreover, the doses of glycerol used in these studies far exceed the 1-3 grams of glycerol (in the form of 65% glycerol-containing supplements) you’ll find in pre workouts.

You see, glycerol is extremely hygroscopic, meaning it attracts water. To prevent this clumping and caking in dietary supplements, glycerol liquid is dried into a powder and mixed with copious amounts of silicon dioxide.

The FDA has set upper limits on the consumption of silicon dioxide not to exceed 2% of food total weight. This is mainly because amounts higher than set limits haven’t been sufficiently studied

It’s also worth mentioning that animal studies indicate that consumption of glycerol monostearate (GMS) increases the exposure to phthalate esters, which can reduce testosterone levels.[53]

For these reasons, AML PreWorkout X-Treme contains no glycerol.

It may be beneficial if you’re training outside in hot/humid conditions for several hours, since glycerol may help prevent dehydration, but for the athlete training in the gym for 60-75 minutes, there is little benefit to be had.

If you do want glycerol, the most cost effective option is to purchase pure glycerol liquid and add it to your pre workout.

Unproven Stimulants

As we mentioned above when discussing caffeine, AML PreWorkout X-Treme does NOT contain any unproven/unsafe stimulants such as Higenamine, Hordenine, or Phenylethylamine (PEA). 

We’ve discussed at length the issues with these compounds in our articles titled:


Without rehashing the entirety of both articles, essentially, the stimulants lack extensive safety/performance research in healthy human subjects.

Furthermore, as discussed in the “Higenamine Concerns” article, the majority of supplements using higenamine failed to meet label claims. And, there are no studies investigating the effects of oral higenamine supplementation on its own on athletic performance in human beings.

For these reasons, AML PreWorkout and AML PreWorkout-Xtreme use only caffeine and surround it with a complementary collection of focus aids and performance boosters that culminate in the consummate pre workout supplement!


Taurine is an amino acid commonly found in energy drinks and many pre workout supplements.

It serves many roles in the body, including that of an osmolyte and antioxidant.

While this might sound beneficial in the context of a training session, research investigating the combination of caffeine + taurine did not find improvement performance, energy, or attention.[54,55,56,57]

However, researchers did note that the combination of caffeine + taurine did negatively impact feelings of vigor and lessen the stimulating effects of caffeine.

Perhaps most interesting, combining caffeine and taurine was noted to increase feelings of fatigue in subjects.


Agmatine is a derivative of the amino acid L-arginine commonly included in pre workout supplements to support nitric oxide production and enhance muscle pumps.

This is due to some animal research indicating that agmatine may stimulate eNOS and inhibit arginase -- the enzyme that breaks down arginine.[58,59]

Theoretically, agmatine could help improve nitric oxide production and blood flow via these two mechanisms, but there is a succinct lack of research investigating the NO-boosting potential of agmatine in humans.

There is some research that agmatine supplementation may have some neurological and/or endocrine benefits, including a reduction in perceived pain[60], but there is next to nothing regarding agmatine and its effects on athletic performance in humans.

As such, agmatine is not included in AML PreWorkout X-Treme.


Pre workout supplements, like athletes, come in all shapes and sizes.

Some individuals want no stims, some want low stims, and others what a pre workout supplement that dwarfs all others.

AML PreWorkout X-Treme was formulated by athletes for athletes using the latest scientific research. The intention was to create an advanced pre workout supplement built to withstand the most rigorous of training protocols, helping athletes push harder and last longer.

If you’re looking for a pre workout to take your performance to the extreme, try AML PreWorkout X-Treme!



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