science nutrition blog

By Robert Schinetsky

Pre workout supplements define a supplement brand, so much so that they live (and die) based on how those products perform. As you can imagine, the pre workout category is extremely competitive with hundreds of companies (and influencers) vying for your attention, and more importantly, your hard-earned money.

This can leave consumers in a bind -- how to decide what is the best pre workout supplement amidst the increasingly polluted pre workout landscape.

We’ll save you a lot of time searching on Google, Amazon or in your local brick-and-mortar…

Discover AML PRE XTREME – the most advanced, science-backed pre-workout formula for explosive energy, focus, & performance. Fuel your workouts like never before!

NEW AML Pre Xtreme is the best pre workout supplement; one that utilizes the most advanced formula based on scientific research in humans.

NEW AML Pre Xtreme is designed to support increased energy, mental alertness, muscular endurance, strength, and lean body mass.^†

What separates NEW AML Pre Xtreme from the competition?

You’re about to find out…

AML Pre Xtreme Ingredients

L-Citrulline (10,000mg)

L-Citrulline is an amino acid found in various melons that is prized for its blood flow- and performance-enhancing benefits. It’s converted to L-arginine, where it’s used by endothelial cells to synthesize nitric oxide (NO) via the L-arginine-NO pathway.

Increased vasodilation and blood flow may help delay fatigue by allowing greater oxygen and nutrient delivery to the working muscles to enhance strength and power expression as well as the replenishment of ATP.[1] Keep in mind that increased vasodilation and blood flow also support healthy blood pressure levels and cardiovascular health.

 Interestingly, while arginine is the direct precursor to nitric oxide, l-citrulline has been shown to be a superior option for increasing plasma levels of l-arginine compared to l-arginine supplementation and comes with less GI discomfort.[2]

Research finds that citrulline may help[3,4,5,6,7]:

●      Improve VO2 kinetics

●      Boost energy production

●      Enhance time-to-exhaustion (TTE)

●      Increase the number of repetitions performed

●      Reducing the rate of perceived exertion (RPE).

 Not only can citrulline improve performance (and muscle pumps!), other research finds that it may help to reduce muscle soreness up to 40% in the hours following training.[5]

Creatine Monohydrate (5,000mg)

Among the hundreds (if not thousands) of dietary supplements available, none has the track record or body of research that creatine monohydrate has. Quite simply, it is the metric by which all other dietary supplements are judged.

Supplementation with creatine, in combination with resistance training, has been shown to support better outcomes (compared to resistance training alone) in:[8

●      Energy production

●      Power

●      Strength output

●      Lean mass gain

Creatine also supports recovery by reducing muscle damage following exercise.[9]

The International Society of Sports Nutrition position stand on creatine monohydrate emphatically states[8]:

 "Creatine monohydrate is the most effective ergogenic nutritional supplement currently available to athletes with the intent of increasing high-intensity exercise capacity and lean body mass during training…

Creatine monohydrate supplementation is not only safe, but has been reported to have a number of health benefits in healthy and diseased populations ranging from infants to the elderly. There is no compelling scientific evidence that the short- or long-term use of creatine monohydrate (up to 30 g/day for 5 years) has any detrimental effects on otherwise healthy individuals or among clinical populations who may benefit from creatine supplementation…

At present, creatine monohydrate is the most extensively studied and clinically effective form of creatine for use in nutritional supplements in terms of muscle uptake and ability to increase high-intensity exercise capacity.”

Not Just for Improving Performance and Lean Body Mass

In addition to improving athletic performance and lean mass gains, a burgeoning body of research is finding that creatine helps support cognitive function, mood, and neuroprotection. Another important point to keep in mind is that although the brain represents only 2 percent of total body weight, it uses approximately 20 percent of the body’s energy. Since the brain requires significant ATP turnover, creatine metabolism and the creatine kinase/phosphocreatine system are vital for normal brain function.[68]^†

A 2024 systematic review and meta-analysis published in Frontiers in Nutrition concluded that, “Current evidence suggests that creatine monohydrate supplementation may confer beneficial effects on cognitive function in adults, particularly in the domains of memory, attention time, and information processing speed.”[64]^†

Traumatic brain injury (TBI) are detrimental to the brain in numerous ways and disrupt typical brain functioning. It’s estimated that 50–60 million individuals worldwide are affected by TBIs each year, and approximately half of world’s population will sustain a TBI in their lifetime.[69] A new review in Missouri Medicine concluded that “...creatine may enhance recovery from TBI, as it directly targets derangements from such trauma.”[69] Prior research also shows that creatine “supplementation reduced neuronal damage, protected against the effects of cellular energy crisis and improved cognitive and somatic symptoms.”[70]^†

Recently a 8-week pilot study found that creatine monohydrate helps support individuals with depression.[67]^†

Last, but not least, a new systematic review and meta-analysis concluded that creatine directly targets myocardial cells to protect their function and minimize injury to the heart muscle.[71]^†

When Should I Take Creatine?

Regarding the “best” time to take creatine, some research indicates that post-workout may be slightly better than pre-workout. Still, other studies find that pre-exercise creatine may be more optimal due to increased blood flow during exercise and subsequent uptake by muscle cells.[65,66]

Keep in mind, though, that these are a limited number of studies, and the much more important factor is that creatine monohydrate is consistently taken (daily).[65,66]

To make things convenient for you, we’ve included a full 5,000mg of creatine monohydrate in every serving of AML Pre Xtreme. And, if you take a serving of AML Post Workout you’ll receive another full 5,000mg creatine monohydrate!

Beta Alanine (3,200mg)

Beta alanine is renowned for two things -- it’s ability to boost endurance and the tingles it induces. For those of you unfamiliar with beta alanine, those “tingles” (technically known as paresthesia) are completely normal, and they usually subside once you’re saturated with beta alanine (which usually takes between 4-8 weeks, depending on your dosing protocol).

 Higher dosages of beta alanine (greater than 3,200mg) per serving can cause more severe “tingles”, which many feel is undesirable.

As for why beta alanine is in AML Pre Xtreme…when muscles repeatedly contract (such as during a high rep set or sprint), hydrogen ions (H+) begin to accumulate in the muscle. As these ions build up, the muscle pH becomes more acidic, which eventually prevents the muscle from being able to contract.

Beta alanine is the rate-limiting precursor to carnosine synthesis, and carnosine is a formidable intracellular buffer that helps neutralize H+ ions.[9]

Essentially, 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 to complete more repetitions and more total work before succumbing to fatigue, which should result in greater gains in performance, muscle and strength over the long term.

To date, beta alanine has been studied across many athletic endeavors, including boxing, martial arts, running, high-intensity interval training, and resistance training, and shown to improve time-to-exhaustion, resistance to fatigue, and muscle growth.[10,11] 

New Study! Creatine + Beta Alanine + L-Citrulline for Better Performance

Most often dietary supplements are studied in isolation. Very rarely are they studied in combination; however, most of us take these various ergogenics in combination, not isolation.

New research published in the International Journal of Sports Physiology and Performance investigated the effects of Creatine (0.1g/kg) vs Beta Alanine (4.8g/day) vs L-Citrulline (6g) vs a combination of all three vs placebo in healthy young athletes.[72]

The athletes performed a variety of athletic tests, including short-sprint interval training (3 sets of 10 repetitions of 5-s all-out runs) sessions 3 times a week for 4 weeks. At the end of the trial, the researchers found that supplementation with the three most common pre workout ingredients, both individually and in combination, significantly improved physical and physiological performance compared to placebo.[72]

Betaine Anhydrous (2,500mg)

Betaine (trimethylglycine) is a natural osmolyte found in a number of foods common to the diet, including whole grains, shellfish, spinach, and sugar beets.[12]

It plays a key role in several aspects of human health, including the methylation of homocysteine. In fact, aside from methylfolate, betaine is the only molecule that provides methyl groups for homocysteine remethylation.[13]

Research indicates that high levels of homocysteine can be a risk factor for heart disease.[14]

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, which encourages cell volumization and cellular swelling. This promotes muscle growth by way of stimulating muscle protein synthesis.

Additional research indicates that betaine supplementation may significantly increase anaerobic power, muscle protein synthesis, and body composition.[15,16,17,18,19]

Beyond its performance and physique benefits, researchers have discovered that diets high in betaine may support certain vital organs (including the heart and liver) and improve ones health.^†

Citrulline Nitrate (2,000mg)

Most pre workout supplements include L-citrulline to boost NO production, athletic performance, and pump. What you may not realize is that your body includes two independent pathways for nitric oxide synthesis. We’ve already mentioned the Citrulline→Arginine→NO Pathway. The other pathway is the Nitrate→Nitrite→NO pathway.

What Are Nitrates?

Nitrates are polyatomic ions composed of nitrogen and oxygen that are naturally occurring in air, soil, water, and some foods, including arugula (rocket), and spinach. In supplements, they usually come in the form of amino-bound nitrates, such as citrulline nitrate or creatine nitrate.

Why Include Nitrates in AML Pre Xtreme?

Nitrates increase vasodilation and blood flow. As we mentioned above, increased vasodilation and blood flow supports increased exercise performance and cardiovascular health.^†

Research on dietary nitrate or nitrate supplements find that it can boost skeletal muscle contractility, peak power output, and mean power outputs in healthy humans.[20,21]

A meta-analysis of six studies including healthy recreationally-trained men and women found that dietary nitrate significantly improved time-to-peak power.[22]

Doses used in the trials ranged from 5.6 to ~13 mmol nitrate (347.2 to 806mg of nitrate). Note: a easy way to convert mmol of nitrates to mg is: 1mmol ≅ 62mg nitrate.[23]

As potent as nitrate supplements are, it’s important to time their intake as they require more time to “load” than other NO-enhancing supplements, such as L-Citrulline. A 2021 narrative review on the effects of nitrate supplementation on exercise concluded that, “Nitrates are an effective ergogenic aid when taken acutely or chronically in the range of ~5–16.8 mmol (~300–1041 mg) 1–3 h before exercise…”[24]

AML Pre Xtreme contains 2,000mg of Citrulline Nitrate (as NO3-T^®), supplying 540mg nitrate.

L-Tyrosine (2,000mg)

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

Supplementing with L-tyrosine supplies extra “raw material” to support neurotransmitter and catecholamine production during stressful situations, such as a high-volume resistance training.

Dopamine: More Than Motivation & Reward

While dopamine is primarily known for its role in feelings of reward and motivation, this just begins to scratch the surface of the many ways in which this neurotransmitter affects health and well-being. It also plays an important role in mood, memory, and motor control. Research even shows that supplementing with dopamine precursors, such as L-tyrosine and mucuna pruriens (which we’ll discuss down below, may also support increased energy expenditure and weight loss.[25,26,27]^†

As you might expect, deficiencies in dopamine can adversely impact motivation, performance, mood, and cognition.^†

Stress (such as intense exercise) can reduce dopamine stores in the brain, leading to increased feelings of fatigue and reduced athletic performance.[28]

AML Pre X-Treme contains 2,000 mg of L-Tyrosine -- the same dose used in human research trials found to enhance mental and physical performance.[29,30]^†

Caffeine Anhydrous (400mg)

“Extreme” pre workouts often rely on a cocktail of stimulants, including hordenine, higenamine, yohimbine, DMHA, DMAA, and/or eria jarensis to provide the “kick in the teeth” sensation that stim junkies crave. However, these stimulants lack the safety data or increased performance metrics of caffeine.

Caffeine is the king of psychostimulants, backed by hundreds of studies demonstrating its benefits in the areas of alertness, cognitive performance, athletic performance, energy expenditure, and weight loss.[31]^†

And, if you’ve had a poor night’s sleep, a higher dose of caffeine (6mg/kg) can offset the decline in performance associated with sleep deprivation.[32]

The world’s most popular stimulant also supports the release of dopamine in the brain as well as upregulates dopamine receptor availability and affinity.[33,34]^†

No other stimulant touts the body of research or high safety profile that caffeine does.

At 400mg per full serving, AML Pre Xtreme provides a science-based dosage and more than enough jolt to get you mentally and physically prepared for whatever athletic endeavor lies ahead!

Velvet Bean Seed Extract (100mg)

To further support dopamine synthesis, AML Pre Xtreme includes a generous 100mg of mucuna pruriens (velvet bean), which contains a natural source of L-Dopa -- the direct precursor to dopamine.^†

This plant has a rich history of use in traditional medicin as a tonic and aphrodisiace due to its broad spectrum of activities. It’s also been found to possess neuroprotective, anti-inflammatory, and analgesic properties.[35]

Interestingly, research in Nutrients, found that mucuna pruriens extract offered greater neuroprotective and acetylcholinesterase inhibitory activity compared to synthetic L-Dopa.[36,37]^†

Newly published research in Brain, Behavior & Immunity found that L-Dopa administration improved improved connectivity within a key brain reward pathway after just one week.[38]^†

Grape Skin Extract (100mg)

Grape skin extract is rich in a variety of polyphenols (including proanthocyanidins) which have been noted to stimulate endothelial nitric oxide synthase (eNOS) and improve oxygen delivery to working muscles.[39,40]

Studies using polyphenol-rich extracts note significant increases in average power (5%), total power output (5%), and maximal peak power output (3.7%).[41] 

Additional research notes that grape seed extract supplementation can reduce muscle damage after high intensity strength training.[42,43]

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

BioPerine (5mg)

BioPerine is the industry-standard black pepper extract included for its ability to improve nutrient bioavailability. Piperine, the primary bioactive in black pepper, 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 and inhibition of MAO.[45,46]^†

MAO (monoamine oxidase) is the enzyme that breaks down mood-boosting neurotransmitters in the body, including serotonin and dopamine. By inhibiting MAO, BioPerine may help dopamine levels remain elevated longer for greater energy, mood, and motivation!^†

Essential Electrolytes

Electrolytes are charged ions that help regulate fluid balance, muscle contraction/relaxation, cardiovascular function, and a whole host of other physiological processes. Two of the most important, in regards to exercise performance, are potassium and magnesium.^†

Research notes that potassium can soften the endothelium and increase nitric oxide production while magnesium aids vasodilation by increasing nitric oxide synthase activity.[47,48]

AML Pre Xtreme supplies 500mg Potassium (from potassium citrate) + 100mg magnesium (from magnesium citrate)

The Benefits of Citrate

Citrate forms of electrolytes have been shown to offer better bioavailability compared to other forms, such as oxide-bound electrolytes. Additionally, citrate has also been noted to improve exercise performance by buffering lactic acid accumulation in muscle cells.[49,50]

Additionally, the combination of potassium citrate, magnesium citrate, grape skin extract, L-Citrulline, and nitrates can offset the blood pressure-raising effects of caffeine in individuals that are stimulant-sensitive.^†

Citrate vs Sodium Bicarbonate

On February 18, 2025, The Wall Street Journal published a piece by Rachel Bachman concerning a new indoor mile world record set by Norwegian Jakob Ingebrigtsen.[51]

Within the article, Bachman states that track athletes are increasingly using sodium bicarbonate (household baking soda) for its blood buffering benefits.

However, large doses of sodium bicarbonate are required, and high intakes often lead to severe GI distress. Citrate supplements, on the other hand, are preferable to sodium bicarbonate because it does not have adverse effects on the gastrointestinal system.[52]

And, research has shown that sodium citrate appears to be a better option than sodium bicarbonate in terms of performance and adverse effects (headaches, GI distress, etc.).[53]

Folate(1360mcg) Folic Acid (800mcg)

Folic Acid (folate) is an essential B-vitamin required for numerous biological processes, including the production of BH4 (tetrahydrobiopterin) -- a cofactor required for dopamine synthesis.

Research notes an association between low dopamine levels (which are linked to depression) and low intakes of folic acid.[54]

Folic acid supplementation 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.[55]^†

BH4 is also required for nitric oxide production.[56]

Essentially, folic acid is a key “supporting actor” that’s often overlooked by competitors. It affects both dopamine and nitric oxide (NO), which (both) can impact exercise performance.

What’s Not in AML Pre Xtreme

“Gray” area stimulants

As we mentioned above, AML Pre Xtreme does NOT include illegal and/or unsafe stimulants that are commonly found in competitor “extreme” pre workouts, such as:

●      DMAA

●      DMHA

●      AMP Citrate

●      Dendrobium

●      Hordenine

●      Higenamine

●      M-synephrine

●      Noopept

●      Juglans Regia extract

●      Eria jarensis extract

For more information on why these stimulants are not included in any AML supplements, read our article titled: Stimulant Warning: "Stim Bombs: Cracked Out!”

No Acetylcholine Precursors

Acetylcholine is an important neurotransmitter involved in learning, memory, and the mind-muscle connection. The neurotransmitter dopamine also plays an essential (yet overlooked) role in exercise where it helps to motivate people and help them push harder during intense physical activity (thereby allowing for greater performance and results).

Nevertheless, pre workout supplements frequently contain acetylcholine precursors, such as choline bitartrate, choline citrate or alpha-GPC, and neglect to include dopamine precursors.

What many individuals don’t realize is that acetylcholine-support supplements may increase levels of trimethylamine N-oxide (TMAO) -- a metabolite of choline that has been associated with increased cardiovascular events, such as stroke.[57,58]

Landmark research published on November 24, 2021 in JAMA found that that use of Alpha-GPC was associated with a higher 10-year incident stroke risk in a dose-response manner after adjusting for traditional cerebrovascular risk factors.[75] More specifically, individuals supplementing with α-GPC vs not supplementing with it had a 46% higher risk of stroke.[75]

Another review on Alpha-GPC supplementation, published in December 2021 concluded that “...GPC promotes atherosclerosis through multiple mechanisms and that caution should be applied when using GPC as a nutritional supplement.”[76]

Most recently, research in Frontiers in Pharmacology found that TMAO may contribute to the development of prostate cancer as it promotes the proliferation and migration of prostate cancer cells by activating the p38 pathway and increasing HMOX1 expression.[77] Based on these findings, the team of researchers conclude that “reducing choline intake through dietary intervention may delay the onset and progression of prostate cancer, presenting significant clinical application value.”[77]

For these reasons, AML Pre Xtreme does NOT contain acetylcholine precursors, like Alpha-GPC. We suggest getting choline, an essential nutrient, from the diet. Eggs or CDP-choline are less prone to be converted to TMA and TMAO than other forms of supplemental choline[59]

No Glycerol

Glycerol is prized for its ability to “hyper hydrate” muscle cells, due to its prominent osmolytic properties. The ingredient gained popularity among endurance athletes who frequently add glycerol (in the form of a 20% glycerol solution) to their drinks during and around training.

However, the research on glycerol and performance is mixed.[60,61]

Moreover, the doses of glycerol used in these studies (1.2 g/kg body weight) far exceed the 1-3 grams of glycerol (in the form of 65% glycerol-containing supplements) that you’ll find in pre workouts.[62,63] FYI, for a 170-lb male (77.27 kg), you’d need to consume upwards of 92 grams of glycerol to achieve the hyperhydration and endurance benefits associated with glycerol supplementation.

No Taurine

Taurine is an inhibitory amino acid that serves many functions in the body, including those of an osmolyte and an antioxidant. It also influences the inhibitory neurotransmitter GABA, which could impede muscle excitation, force production, mental energy, or motivation.

Furthermore, several case reports have shown that the combination of caffeine + taurine in energy drinks can cause elevated blood pressure, ventricular arrhythmias in sensitive individuals and sudden death![73,74]

For these reasons, taurine is not included in AML Pre Xtreme. It is best taken as a health-supporting dietary supplement without co-ingestion of caffeine.

AML Pre Xtreme: The Best Pre Workout Supplement

Pre workout supplements are a dime-a-dozen. They can be found in virtually any big box grocery store, club store, or online retailer. When deciding which supplement to purchase, there are many factors to consider, including your budget, supplement facts panel, the company releasing the supplement, and where that supplement was manufactured.

AML Pre Xtreme spares no expense -- using premium ingredients backed by research in humans. No other supplement can match this advanced scientific formula.

For optimal exercise performance & results, consume AML Pre Xtreme 1 hour before exercise. For added recovery and growth, take a serving of AML Post Workout immediately after training, before a post workout meal that provides all the essential amino acids.

^{© Published by Advanced Research Media, Inc., 2022}

^{© Reprinted with permission from Advanced Research Media, Inc.}

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